The last few days I've been unable to open Illustrator. It either immediately crashes, or gets stuck in a loading screen of "we are processing your request". I've tried reinstalling it, I've tried installing an older version. Nothing is working. It won't even close when it gets stuck, I have to force close it through task manager.
Sorry about this trouble. I am hopeful that the issue was fixed. If not, we have recently released an update for Illustrator 2020 (v 24.3) which contains some stability fixes. If you are not already on v24.3, then we recommend you to update to latest version.
If that doesn't help, try steps shared in this help article and share your observations with us.