Presumably determining if a loss leader exists to destroy competitors is tricky though?

Like, MS aren’t going to come out and say “we want to bury gitlab”, even if that was the intended goal. there’s always going to be some vague brand building excuse to hide behind.

(I don’t think this is the case for GitHub, but to illustrate the point)

It is somewhat tricky, but sometimes it can be (and has been) proven; people do say all kinds of things while doing illegal stuff, and sometimes even write it down or send it as an email.

This is a good point — the LIBOR scandal springs to mind when thinking of the inexplicably brazen things written down whilst committing white collar crime!