this software isn’t available in the selection that Fedora/Ubuntu/Mint/whatever
My man, those repos are vast as shit. The only time you will run into this situation is either if you’re using obscure software (that most newbies won’t use, and then again if you can’t Google a few things you shouldn’t be using obscure software) or stuff that isn’t supported on linux at all.
limiting user choice
We aren’t limiting user’s choice. You can do literally everything you want on Linux, just need to know how. You need to know how to do stuff in other OSes too btw, but doesn’t mean they will let you do everything.