I've been a bit taken back recently as to how buggy Visualize is. As I push more models into my session, I'm having a lot of crashes and stalled previews as well as when updating a SW model - appearances and decals freaking out. I just hope that Development is aware of these issues and isn't surprised when they hear of them and that you're getting plenty of SR's written up against them. Haven't read the SPR list for Visualize 2021 but has development been able to address some of these issues with 2021?
I have my RTX4000 workstation but also my Dell Precision 7540 and I see the same issues on both. In fact, recently I've been having more issues with my RTX4000 sessions. Is it possible that a windows graphics driver auto update could be the reason?