But that isn't how it works right? You send your pull requests to the relevant maintainer, CC people that you think should be aware _and_ send it to the mailing

But that isn't how it works right? You send your pull requests to the relevant maintainer, CC people that you think should be aware _and_ send it to the mailing list (probably also "only" via CC). This here for example is sent to Linus directly and that part does _not_ depend on the mailing list. The mailing list is just a convenience feature for people that _want_ to be aware but may be looked over/forgotten by the submitter (which still happens, and people regularly say stuff like "also CC'ing additional relevant people"). Yes you could, at least in principle, also do that via GitHub/GitLab/whatever. But a) you wouldn't gain anything (the kernel already has all the tooling it needs and it's large enough to just create missing tools, heck git was literally written for it), b) you would introduce a massive single point of failure that either i) is _not_ under control of the kernel.org team or ii) needs a massive amount of resources to host (see the fun people poke at displaying 2k commits in GitLab). Neither seems like a good use of the kernel development resources. And if you want to contribute to the kernel... using a mailing list is an absolutely trivial problem.