No idea why the OS of someone should be better than your favorite distro. Sounds like bull shit.
But, the docker version is a second class citizen for home assistant. You have to manually install stuff yourself. Which is usually no problem but the how tos and tutorials etc. Aren't as easily visible and hence it's unneccessarily complicated in my opinion.
If you install it via docker and it's the first time, you won't know that the stuff is missing. Look for how to install HACS.
I'd always go the container route. You can just move the files to a new server, you can spin it up and down, install a second isntance, back it up, share it with friends. Containers are awesome.