> the actual motivation of hitting people with legalese and takedowns isn't to literally take the software down, it's to drive up the cost of development, and to get people who maintain it to quit, which is probably why we're in this thread

This only does anything useful to them if the software and all of the forks stop being maintained, regardless of whether the people doing it now are the same people who were doing it before. Which is one of the reasons why it's important to replace them, to deter this kind of attack. But they have been.

> given that software like youtube-dl basically needs to be permanently fixed to even work slowing down development is enough.

Not really. The demand for having youtube-dl or equivalent work is orders of magnitude higher than the amount of effort required to make it work.

Attacks like this also fortify development efforts because of the Streisand effect and the increased effort people are willing to put into something once it becomes a matter of pride to spite the attackers.

I think there should be new legislation to prevent such targeted nuisance takedowns, in a similar way to nuisance lawsuits.

Current legislation doesn't permit that specific takedown anyway, the procedure to remove a copyright infringing tool requires a court order. I still don't understand why anyone paid attention to it at all. The best I could find on it was that the RIAA was arbitrarily claiming they had the right.