Do you have some examples? Most things I (and others) do are in the category “showing a desktop”, multiple desktops with different resolution / scaling / refresh rate, maybe opening a virtual monitor using krfb.
Wayland has been a complete game changer for me regarding performance and reliability (as soon as it hit a certain stability lol).
Okular works so well at this point that I use it to annotate all my PDFs if I don’t explicitly need free-hand drawing (and xournalpp otherwise).