This may not be a one-size-fits-all situation, but virtualization definitely is a likely factor in my current issues (Macbook Pro - 2019 - 10.15.6). It does NOT only happen with external monitors (in my case), so I ruled out that factor early in my process. Oddly enough, I actually recently requested that my employer purchase VMWare Fusion for me because I was having such major issues with Virtualbox stability (and blamed VBox, not MacOS). I also now have VMWare Fusion running on my older MacBook Pro (2015 -- running 10.15.3 <-- important!!) and it runs 24/7 without any panics/reboots. I am definitely blocking any MacOS upgrades on my old one!! :)
Turning off Spotlight completely, along with unchecking power-saving options, DID seem to give me slight improvement with my newer MBPro, but maybe this is simply related to overall memory management, and how quickly MacOS needs to go into "panic mode".
Thanks for passing that link along -- definitely makes me think that this may be the ultimate root cause. Would be very interested to see if virtualization is a common denominator with other folks experiencing these constant kernel panics and watchdog timeouts on Catalina 10.15.6.