In theory, but who uses something other than either Github or Gitlab?

Obviously I know some people do, but I've yet to work on a project that doesn't just stick with the one.

I believe everyone here is talking past each other. Decentralization doesn't just mean hosting. My copy of git repo is equally as valid as yours. Or, the master branch is nothing special, any branch is equally as important. In that way, it is decentralized.

But, as you're saying, rightfully, hosting of the remote repository is in the hands of Github. So its not decentralized.

These discussions tend to be like the ones involving 'conciousness'. Until a clear definition of the term is agreed upon, it is impossible to talk about it. Going around measuring with a yard stick requires that the stick is calibrated to a yard and everyone agrees it is a yard. May be you can do some probabilistic measurement (consensus of people whether something is decentralized or not), but it's pretty useless.

Interesting that when given a choice, people choose centralised over decentralised.

That's because of economies of scale. It's much cheaper/easier to do something when it's the only thing you do. It's why we have professions, rather than each of us doing a bit of everything.

i think this is mostly because of the maturity/popularity of the tooling, not the underlying aspect of centralization. if there was a just as slick, widespread and useful decentralized alternative, i would be on that instead.

Depends on what problem the adoption of decentralisation is solving. There's no point choosing a decentralised option just for the sake of it.

i think i would choose decentralized almost all of the time if it worked the same performance wise

Sqlite

https://www.sqlite.org/whynotgit.html

I've heard of companies that pass their git repo around on a USB disk? lol.