I'm a scientist myself. It's quite clear from where I'm standing that to get good jobs, research grants, etc one needs plenty of published articles. Whether the conclusions of those are true or false is not something that hiring committees will delve into too much. If you are young and have a family to support, it can be tempting to take shortcuts.

Most of the "proofs" that you talk about are by crackpots who have published almost nothing before. This guy has 21 publications according to mathscinet, some of which are in relatively prestigious journals. So we should take this a bit more serious than the RH proof spam on the arXiv that the parent talks about. That said, it has happened before that a well respected mathematician has announced a proof for the RH that has turned out to be false (de Brange comes to mind). So the jury is still out on this one.