How effective is it against people who just simply does not care?

I suspect people are doing it to pad their resume with "projects contributed to" rather than to troll the maintainers, so if they're paying any attention they probably do care...

Most people do, and those who don't still get banned so...

what you say, is of course the only relavent issue. I can attest to my own experiences on both sides of this situation, one running a small business that is bieng inundated by job seekers who are sending AI written letters and resumes, and dealing with larger companys that have excess capacity to throw at work orders, but an inability to understand detail, AND, AND!, my own fucking need to survive in this mess, that is forceing me to dismiss certain niceties and adhearance to "proffesional" (ha!), norms. so while the inundation from people from India(not just), is sometimes irritating, I have also wrangled with some of them personaly, and under all that is generaly just another human, trying to make by best they can, so....