imho

1. budget
2. screen size
3. specs (based on your use case)

well, i guess you can go for 65 inch X80H (decent TV for casual use)

If dont play ps5 or xbox in future.. No use in getting x90h.

Yup..once u go big...you would not want a smaller screen size.

But viewing distance is also important.

i cant advice u for atmos. as i dont use it. i am still using 5.1 only. does atmos work without earc? i not sure about this. coz i believe there is no earc now. waiting for firmware update.

my reason to get x90h 55" over x80h 65" is for the FALD feature and the higher quality panel. if u prefer size of feature, then x80h will be suitable for u. Side by side, I see very little diffference at least on demo. I suspect with darker scene movies, the absence of FALD will be felt more. But this is a case only if u watch in a dark or semi dark room as it is in my case. If u watch in a well lit room, this is not so much an issue i think.

your budget for x80h 75" can probably also get a x90h 65" plus 1k pocket change

If this happen in SDR ,  disable local dimming , set it to off .
If this happen in HDR , there is nothing much you can do except to turn off the subtitles .
Sony's  LCD TVs don't handle subtitles very well , unlike the Samsung LCD but they come with a cost of crushing smaller highlights .
There is no perfect solution on LED LCD TV currently .