That's a pretty good warning, though! People use remote access software like TeamViewer to scam people out of money constantly, there's entire offices where people go to work just to scam people out of their money using this software.
It's such a huge problem that it really does warrant all of this attention.
Nope, it's a huge problem for all of them, it has been a huge problem with TeamViewer for ages. However, putting these large banners up likely helps ensure that it's actually not a huge problem for Rustdesk. It's more likely to be a huge problem for services that don't put up these banners. That's exactly why you put up these banners, you don't really want to be a part of enabling these scams.
It's such a huge problem that it really does warrant all of this attention.