Strong disagree on this.
We live in a society, to operate open communities there are trade-offs.
If you want to live in a miserable security state where no action is allowed, refunds are never accepted, and every actor is assumed hostile until proven otherwise, then you can - but it comes at a serious cost.
This doesn't mean people shouldn't consider the security implications of new PRs, but it's better to not act like assholes with the goal being a high-trust society, this leads to a better non-zero-sum outcome for everyone. Banning these people was the right call they don't deserve any thanks.
In some ways their bullshit was worse than a real bad actor actually pursuing some other goal, at least the bad actor has some reason outside of some dumb 'research' article.
The academics abused this good-will towards them.
What did they show here that you can sneak bugs into an open source project? Is that a surprise? Bugs get in even when people are not intentionally trying to get them in.