I have a 2019 16" MBP and too feel this pain... I'm typing this from my 2014 15" MBP running Mojave... I used to use this for everything and now use it for most things and my shiny new 16" for tasks which this one can't handle as well. I wish I could merge the two. I've looked into everything and managed to install a back up of Mojave on a virtual machine. I've used Fusion and Parallels... the later works better in my opinion. Just mentioning it in case you fancy running Mojave that way. It works for me with some apps but not others.I bought a 2020 27" iMac a few months ago. Unfortunately for me, it came pre-loaded with Catalina. So it was either the POS Catalina, or somewhat POS Big Sur. I'd *MUCH* rather had the choice of sticking with Mojave.