More crowding also means more CPU demands.
Zwift did say this (linked below) about crashes on Nvidia systems recently but I’m kind of doubtful it’s what you are dealing with. On an Nvidia system you should be safe with the driver provided by Microsoft, no need to update it with anything newer from Nvidia. You should also make sure you’re not burdening the CPU with anything other than Zwift, like Sauce or OBS, while you are troubleshooting this. You could upload logs to zwiftalizer.com and post results here or on the ZPCMR Facebook group.