Never got any jobs through any of them ever and I’ve been in the workforce a long time. The straw broke on the camels back when I read a post today from a third party recruiter criticising candidates for not making their applications stand out enough during this time. This is not the time to do that, you just give all recruiters a bad name and proved that you only work for commission/the employer and never cared about candidates in the first place.
Bottom line - most third party recruiters only work for their own interests and have no empathy. The odd ones do, but they are few and far between.
Everyone works for their own interest otherwise it would be charity.