It also dissuades other people who may not make mistakes from contributing. I’m certainly not getting involved with a community run by someone who mirrors past abuse I’ve experienced, for example.

Then it's an inefficient method to do so, because along with discouraging these particular people, it may also discourage many other productive and competent developers who don't wish to condone this sort of abusive leadership.

Perhaps the intention was to discourage the kind of people that are easily offended from such "abuse".

Unless there's some demonstrated correlation that this subset of people is likely to be less productive contributing to a project like Linux, then this would just be bad leadership on behalf of Linus who'd exclude potential contributors based on personal whims.

You might consider simply emailing back with "please don't make mistakes contributing to the project". That works really well with me and everyone else I know. I don't need to be bullied to be convinced.

Then that’s not a particularly nice thing to do. People naturally make mistakes, and I’m pretty sure that the consensus is that belittling them when they do doesn’t really help.