Real life software is much more than just downloading a game and running it.
Rebuilding? No. Linux package management is so-so at allowing you to compile programs. But they’re dogshit garbage at helping you reliably run that program. Docker exists because Linux can’t run software.
There's a reason everyone uses it for ops these days, and not some Windows thing.
> it’s not trivial to manage the whole environment needed to run the application
This is a distinctly Linux problem. Despite what Linux would lead you to believe it is not actually hard to run a computer program.
Real life software outside of Linux is pretty much just downloading and running it. Only in Linux we don't have a single stable OS ABI, forcing us to find the correct package for our specific distro, or to package the software ourselves.