With it's design of what mods should be like... That's the point you people are trying hardest to dodge. Mod packs limit which mods can be installed into a .jar due to forced configurations of said mods. Not everyone wants the same configuration that you are promoting, and you are trying your hardest to not acknowledged this.
THAT is a big reason to not use mod packs: because if a mod is not picked up by a 'famous mod pack', chances are great that said developer does not gain fame for his work. Hell, even one of your own said he was tired of working on his add-on/standalone mod because he has remained unknown for three months. I can easily say that it was due to being lumped into a clusterfuck of other material for users to siphon thru, and literally was lost in the content you provide.
So if Techinc becomes the primary download source for players who want mods, how long do you think it'll take users to forget about Alba, Spacetoad, Eloraam, and the rest of the Forge team? (assuming you care, of course)
Going to assume you are referring to Power Crystals whose primary reason for leaving the modding community is that the dude is no longer unemployed and has a stable job now and would like to actually interact with people in what little spare time he has instead of crunching away at code. If he was leaving because he thought that Technic was making him fade away, I really do not think he would let Technic have the source code to keep his mod up to date and available to the community.
I'm not sure I understand your other point though. Before technic, if you wanted to get the mods running that are in that pack you would have to do a bunch of bullshit mucking around with Block ID errors and class file incompatibility. Technic has made it so that this isn't even an issue any more. Yes Technic only allows for a few mods to work together, and I get your point there, but for the most part, the majority of the mods out there do not work together. This is not a fault of the authors, but more of Mojang having waited so long to work on a mod API when they've known they have had a growing modding community on their hands. Honestly I could have kept NPCs out of the game until after they hired their AI programmer and instead had Mojang work on an API sooner.
Now, mod packs are not making this situation worse, rather they are a somewhat clumsy answer to the limit put on the modding community by Mojang's lack of support. It is unreasonable to ask all modders to make sure that their mods work nice and clean with others, in fact I would say that it is almost impossible. So because of the fact that Mojang has not been supporting the modding community we have an issue where there are a lot of awesome mods and some of them seem just right to work with each other, but because of technical limitations, they do not. So do you just tell the community to go shove off and deal with choosing one mod or the other? Or do you start looking for other answers. Currently what we have are people compiling mod packs, yes they are limited in scope, but for the same reason why it is impractical to ask mod authors to make 100% open compatible mods. These mod packs allow users to select numerous mods that they would normally would only be able to use one or so at a time. This allows multiple developers to be exposed to the public at once and you cannot tell me that the mod pack is stealing away attention from the developers when the mod pack authors refuse to take credit and keep pointing back at the original creators of the mods (even if certain mod pack authors could use better PR and be a bit nicer when dealing the community ).
So now we are coming to a situation where there are a few really good mod packs that covers several ways to play Minecraft modded (example would be the YogBox tailoring towards RPG Adventure style gameplay while Technic tailors to those who enjoy tech trees, industrious building and mega projects. Basically your survival adventurer and your builder). Some mod authors have been very cautious about this, which is an odd situation I've only seen in the Minecraft community (I used to develop mods for Morrowind and dabbled shortly in Oblivion) and I kind of blame this on the Curse forums having decided to force mod authors to include templates of VERY poorly written "copyrights" with their mods especially when the whole current legality of Minecraft Modding is in this shaky grey zone. So because of this we have Mod Developers who have grown to be, I would almost say, over protective of their mods and are cautious with this new change to Minecraft Modding called mod packs. However, as time has gone by those same developers are slowly realizing this is a good thing, as other people are doing the work for them for making compatibilities between other mods (giving them more time to work on making more content for their mods!) and they are learning from it. We have developers starting to talk to each other and from this we had the community as a whole going "Hey, you know what? Mod compatibility is an issue, Mojang IS dragging their feet on fixing this issue, what else can we do to make it so that the users of our mods can enjoy any mod they please without worry of having Minecraft breaking on us." And with that we have seen such things as Forge beginning to be be developed.
The other thing that mod packs have allowed, and this a very recent thing, is SMP playability. Yes some mods do come with a SMP version, but usually the mod works with only itself installed on a server. Then there is the issue when you ask a mod developer if they will make their mod SMP playable they usually respond with "maybe, don't expect it anytime soon" and more often than not with just plain "no" because it does require a lot of extra codding, now ask those developers who said they would make SMP version if they would make it Bukkit as well and that is almost always met with No. With Tekkit we have a great list of mods that have been not only made SMP capable, but have been converted to Bukkit, have been compiled into a ready to launch Server set up that will pretty much run on any OS under the sun and thanks to the awesome folks working on Spout, an incredible client launcher.
So yes, I think that mod packs are a great thing, no I do not think it is hurting mod developers, and no I do not think it is anything to get twisted over because this is just the community reacting to fill the holes Mojang has made until they can get their shit together. And isn't that what most of modding is about? Filling in the missing parts you feel a game has? Come a month of so after the release of the official mod API you will see mod packs less and less often, though probably never fully disappear. That is because packs like Technic are more than just a quick and easy install of a collection of mods, they also contain tweaks and minor mods that would not exist if not for the pack so that the mods included more seamlessly work together and projects like Tekkit will probably stay around so that we can provide some of the amazing SSP mods to Bukkit SMP servers.
In short I guess, don't hate the mod pack, hate the poor planning from Mojang that made the need for such compatibility work around needed in the first place.