Ubuntu Software Center missing in 20.04
Solution 1:
Same thing happened to my ubuntu 20.04. The software center just went missing and along came out snap store. When I opened snap store, it is very similar with software center and it is doing the same job well. I think it snap store is now the de facto replacement for software center.
Solution 2:
The below steps worked for me in Ubuntu 20.04
sudo apt update
sudo apt install ubuntu-software
Then go to Activities to search for the Software Center once the installation has completed.