So, build speed basically doesn't help habitats at all, since you can build multiple at a time. Before this change, this perk was useless for habitats. And, gave +100% # of ringworlds/other wonders, reduced to +66% once you have unity ambitions, so basically was as strong as galactic wonders itself is.
Anyway, now it gives +50% ringworlds/other wonders, +33% after unity ambitions, and +25% habitat size (which is actually more like +33% output). So, first off, how do you get "tied completely to habitats" when it helps other wonders just as much?
Second, it still gives guaranteed access to mega engineering, which is still useless for habitats, but allows you to get started on other wonders.
Third, if it was "as strong as galactic wonders" before this change, and they add a habitat effect to it... It would now be stronger, when you have both, right? Galactic wonders is already one of the strongest perks, and master builders would be even stronger.
So, now it's a little weaker if you have just galactic wonders (but still strong at +50% imo) (AND you still saved a perk from before since there's no ring of life anymore), about the same if you have just habitats, and really strong if you have both. Sounds like a good design to me.
But, I understand no one is ever happy about their particular playstyle being nerfed. Personally, I just finished a game where I had galactic wonders, but no habitats. But, I try all different playstyles, so no biggy for me. I'm about to play a habitat+ringworld psi empire with size 250 fleets, I think