in my case, scrolling gets very choppy. In YouTube’s video page, scrolling down to see comments will make the page rendering stutter much.
I never experience any audio issue in youtube, but I often get robotic sound from my colleague if I try to do peer programming using Google Meet screen share, while running iOS and Node builder.
Only happens with Safari. The same issue won’t happen on Firefox, even with >20 active pages.
MBP 13" 2018 8GiB, latest Catalina, latest public Safari