This is far from the first (or last) time he wrote something like this. This was just a regular thing in the kernel world for a long time (until Linus matured a little).

Whether or not it was a good thing is up for debate I think. Yeah, it's very rude and unprofessional (and discourages new contributors who don't want to risk getting chewed out), but considering the importance of the Linux kernel, it's good to know the lead maintainer is doing too much of the right thing than not enough (i.e. being lax with bad code in order to be respectful). I'm fine knowing that a few tech workers got their egos smashed if it gives me confidence that the code powering civilization is high quality.