I am excited to let everyone know that Ansys 2021 R1 installs just fine on both Ubuntu and PopOS 20.04.
Unfortunately, after installation I had a problem running the runwb2 script for Ansys 2021 R1. The runwb2 script runs just fine for Ansys 2020, so I'm surprised that the 2021 version did not work. It is likely possible to fix this by editing the runwb2 script, which I have not done. I typically run Ansys Mechanical in batch mode on this Linux computer so I don't need the runwb2 script. Let me know how Ansys 2021 works on your Linux computer.