And people wonder why 1.7.10 is still in use. Some people want to call 1.7.10 dead for modded minecraft.
Seriously though: I thought BC and RC were updated. I know Mystcraft is now up to 1.11.2, and Binnie's now has active developers.
But I also thought that Aznor was out of modding, so Thaumcraft is kaput. I think you're more likely to see a port of ChromaticCraft.
As far as I'm concerned, 1.7 is still a viable option for stable gaming. Lot of polished mods to choose from, most of which have been tested against each other for compatibility quite extensively, means changing up your experience within that version is quite simple and very rewarding. On the other hand, any bugs you find are unsupported, and you miss out on all the cool upcoming mods on the scene. It's dead in that people have moved away from it as a current modding platform, but still very alive to play with.
Last I played with it, RC was unfinished to say the least (missing all the multiblocks, amongst other things), but the basic tenants of rails and signaling seemed intact. All reviews I had heard from BC was that it was still a hot buggy mess, although I've not followed along with the progression in some time.
So far as Thaumcraft, Azanor did indeed step away, but there was some rumbling that @MjJty was looking to keep it alive, but I'm not sure if that discussion ever went anywhere.
Are you suggesting
@Reika is planning to update his suite, or was that a "when Hell freezes over" kind of statement? I haven't been following those threads in ages. Oh, how I would love to play with Rotarycraft again.