I have never experienced an issue with any adobe app. But I've tried to paste elements and vectors from ai to XD and is not working. I already tried to uninstall and install XD, installed older versions and it's keep happening the same 😕 .
Assume you tried just the simplest of elements from Illustrator to be pasted into XD? Just want to eliminate what you are copying did not contain something that might be unsupported? Also have you pasted the element into a new Illustrator document, reselected it and tried that paste?