I have both S&X and the Y is my favorite. IMO it's the perfect size for a large city and the power of the LR is more than sufficient for me.
I think you get a fairer comparison with the non-perf Y against the non-perf X and the Perf Y against the non-perf S.
A non-perf X goes 0-60 in 4.4s, which is comparable to 4.8s of a non-perf Y.
A non-perf S takes 3.7s, which is basically the same as the Perf Y's 3.5s.
Of course, the Perf X is 2.6s, while the Perf S is 2.3s, so if you want to spend much more money, you do get something for it. But it really is a lot more money.
A non-perf Y is $46k, while a non-perf S is $75k and a non-perf X is $80k so why are we even comparing them?
A Perf Y is $60k while the Perf S and X are $95k and $100k. Again, not even in remotely the same price range.
Actually, the difference is greater, in practice, because the S/X have more options to upgrade to, including interior colors. The bigger tires on the S are $4.5k all on their own.
My Y is Perf and FSD, which bumps it up to $68k even before the premium for go-fast red and the hitch. Add in the assorted fees and taxes, plus the nearly $10k I spent on detailing, tinting, PPF, and ceramic coating, and we're talking serious money.
I'm sorry, but while I can, in some sense, afford an S/X, I can't reasonably justify it. The Y is plenty of car for me; if I was being honest, probably more than I actually need.
Thanks for encouraging me to think this through and do the numbers. I think that, if I had to do it over again, I'd go the same way. Of course, ask me again after Battery Day, or as we call it Buyer's Remorse Day.