It's been a while. The last thing that was an absolute mess was screen sharing via Google Hangouts/Meet. You could share individual windows just fine, but I had two external displays attached to my notebook and wanted to share a single screen. It wouldn't work. You could only share both screens at once, so it was impossible for others to read anything.
I think external displays in general had problems, but I don't remember many details. I had problems with my docking station under Wayland, scaling options that didn't work. And there was an issue when trying to re-order attached screens with the corresponding Gnome tool.
I think this was on Ubuntu in 2018 or 2019, when they started giving you Wayland by default. But they soon learned that it just wasn't ready yet.
Granted, some of those problems might have been caused by Gnome tools or Ubuntu or maybe even hardware drivers. But all of them were gone immediately once I switched back to X.