Of course, Mindcrack people decide to comment from that perspective despite specifically being told what the conversation was in the title...
That part of the discussion is cogent, because it supports your point - namely, that IC2 alone can be left out of your modset without missing essential functionality (particularly with MP). GT is what revitalizes IC2 for many people. They, like you, might not use it otherwise. Of course, "people" aren't necessarily as restricted as you make it sound (those .. people). I have a DW20 world, MC world, Magic, MultiMC mod test, etc. They all play differently and have their own benefits, drawbacks, and self-imposed goals.
Ultimately the question is odd. Like most reasonable folks - if you don't enjoy how a mod fits within the vibe of your specific map, you simply don't use it.