Also when did any Linux distribution anytime locked up their own version of MIT tools without sharing the source code?

I mean RHEL has been kinda doing it with GPL for a few years. They share the code with you if you have a subscription, since they have to, but if you share it with anyone, they'll void your subscription contract. With MIT you can skip that scheme altogether and just make version closed source.

Like... Why else would they use MIT here? They could have just used GPL for the Rust coreutils.