what now?

I suppose you could use them all up with lockstyle vanity sets, but.... yeah.

Looking at my primary jobs of SMN and PUP, their set usage is fairly similar, but ill put down what I use for SMN:
base set (for lockstyle)
Idle set (perp/refresh gear)
BP delay set
BP damage set (could get more involved with this, but it wouldn't change a whole lot)
TP set for Gate of Tartarus, really the only one I care enough about optimizing to do so, so in actuality I just use it for all staff WS. I have no reason to make sets for other weapons as any other job can do them better.
That's five main sets, and while I could certainly create more for odd situations / lesser used WS/abilities, I just really don't have a lot of reason to. A lot of these special situations I have covered with macros that change one or two items. Some jobs definitely need more, but if I had just 5 for every job, that still leaves 90 free equip sets to play with to cover more situations, or vanity sets.

Excluding a copious number of vanity sets, I don't think even someone playing all 22 jobs to a moderate level of proficiency needs 200 gear sets. When you include the complete set of macrobooks, which for some jobs and some people can adequately cover a chunk of your gear changing needs, that pares things down more. I think you've forgotten that you can use /equip macros when you only need to swap a few things. Most of us do not play every single job to a serious level.

I accept that a few of the most hardcore players might need more but I expect that most such players have already found other solutions, which can't be named here.