I guess, but the huge ambiguity of it to me, that I think should be resolved, is
is it the future of the project? However controversial it was and respectful it is to give me the choice, my choice is that I want to do what's going to be best supported by the first party, what does upstream expect me to do, especially as a newcomer just trying it out.
(Again, rather. When I first tried it out flakes didn't exist. And actually that makes it even more confusing because the nix profile, nix env stuff I dimly recall is apparently deep plumbing nobody's really expected to use directly any more.)
Maybe the answer is no flakes, because it's disabled by default after all. But then it really does seem like everybody uses flakes now.