It is significantly less powerful when compared to LibreOffice, lacking support for many features. It offers less applications than LibreOffice. It is significantly less customizable than LibreOffice. It’s built on bloated web tech. It lacks RTL support.
I am not paranoid about OnlyOffice’s origin. I also do not think it is the best office suite on Linux by a mile.
Yeah. xwayland isn’t gonna die ever probably, so there’s no rush.