roderickh:
I have the about the same distance and have gone with a 65" with no regrets... Albeit my wall space is actually limited to a 70".
Will you use the OLED advantages i.e. watching in dark conditions, or are you looking to capitalise on the hdmi 2.1 features?
https://www.sony.com/electronics/support/articles/00246472
Dark conditions yes. Not too fussed on 2.1 Primary use will be as main monitor for WFH and occasional movies/netflix.