With the way RDN2A2 is more efficient, and that double side chip cooling patent, perhaps Sony could squeeze out a higher TF number, comparable to the XSX by increasing the clock speed?
I guess they could, but then there's nothing technically stopping MS from doing the same. Same architecture, same node process, same high-end components etc. But there's likely a logistical reason they've settled on 12 (for now) and there's only so far Sony can push the chip before thermals are negatively affected.
So if the PS5 is around the 36/40CU size (just going from Oberon stuff, and some speculation. It might be bigger than that), they can shrink the TF delta but there's probably going to be a limit.
My take: PS5 has lower TF number than XSX, but not by much.. around 11 maybe. Nevertheless.. Even though it ships with lower TF count, it makes up for it in smart architectural nuances i.e. the larger compute in PS4 APU compared to the norm at the time. Cerny is a smart man, he (as the opposition ofc) knows fairly well what's needed down the road. TF's isn't be-all here. I would rather have a SOC that's optimized towards the functions that are actually used by games instead of a raw TF benchmark monster. My bet is PS5 will perform better than XSX even tho' it calculates less TF's. Chew on that!
What is this idea that MS is simply throwing brute force at the problem? They're working with the same architecture and technology Sony more or less is, and they have access to the same GPU features , etc. Yes there're some things they'll both have to do custom API implementations on to provide access to them for developers (variable rate shading, for example), but that should likely come to around similar overhead for both sides (or maybe one has notably lower overhead on some things and the other has notably lower overhead over others).
You're right, TF's isn't the end-all-be-all and it's nice to see people actually keeping that in mind. But there isn't any magical implementation of APIs or optimizations that will somehow result in PS5 running rings around XSX in terms of efficiency of resources used. Sony has a great lead in someone like Cerny, but it's not like he has no equivalents on the MS side of things (and I'd suspect both companies are pulling engineers and architects from relative divisions to their PS/Xbox ones for next-gen console development).