Some of it, yeah.

All a distro is, really, is a preset. It comes with some package manager or other, along with a collection of pre-installed packages.

The reason one chooses one distro over another, is because it's closer to what you need. I could install arch, and spend a day setting it up exactly the way I like. Or, I could start with Endeavour, and get to essentially the same state in an hour.

I'm familiar enough with linux that I could strong-arm any install into doing whatever I need, but at times, to get from preset A to preset B, it's faster to just start over from a known preset that's closest to what I want.

Rolling releases typically mean the software available is recent, but that's only one aspect of what your starting point could look like.

"Gaming" distros are going to be a preset that contains a bunch of configurations, defaults and software, that gamers typically care about. That steam is usually already installed, is an example of one such thing. The same way my mention of GPU and CPU support is only an example.

Maybe instead of "They tend to make sure stuff that gamers care about are up to date and working" I should have phrased it "They tend to make sure things that gamers care about are easy to set up and supported, if not even ready to go, out of the box".