Catalina from Mojave BUT tries to load Big Sur!?

When did Apple lose the plot?

I have a late 2012 Mac mini (server) with 16GB Ram under Mojave. Preferences says I need to hydrate to Catalina.

SO I go look see Catalina BUT it tries to load Big Sur! (Issue 1)

Issue 2 - It is my understanding that Big Sur is not "right" for my poor Mac Mini

Issue 3 - The Big Sur Front page on App Store says that it "works on this machine" BUT changes within a couple of seconds or after "v" to "OS X 10.9 or later"

Issue 3 - But where, now, is Catalina?

And here am I, all my data backed up and ready to get married but where is the bride?

Meanwhile please point me to Catalina...

Come back Steve Jobs - things seemed so much simpler then?

Terry B