Wow....so this makes me realize that it has been a while since I worked a desk. I admit that. But I still have an opinion. And it's complicated.
I am sure that recruiters could point to a large number of hires they made, good hires, where if they had searched the person online, they would not have hired them. We look at online info about a person as evidence of how they "are" but it's really just how they "were." I am not that embarrassing girl from the 80s. Ever do or say something you regret? Online? Yeah, me too.
Some recruiters start out looking for a reason not to hire someone. I'm not sure why they do this other than an ego-driven hazing ritual. I like to hire people. I do my due-diligence to make sure we are hiring the right people but I tend to start from a place of "yes." So if I decide not to hire someone, the reason is a good one. And it is notable how fast a "yes" can turn to a "no" in an interview, but anyway. A lot of the stuff you find online about people does not constitute a good reason, in my opinion. So what if your candidate likes to dress up in a bunny suit as long as they don't do it at work? They call it "personal" time for a reason. I don't judge.
I think if companies want to do some sleuthing, they should have a consistent back-ground check program and if some of that includes online fact (or picture) finding, that's OK. I can imagine some egregious stuff is out there (and I am not saying to overlook it) but I think that by-and-large, people (recruiters, hiring teams) are getting scared off by beer bongs and strongly worded opinions. Perhaps a little more open-mindedness and a dose of reality are called for. Because seriously? Seventy percent of recruiters have chosen not to hire someone because of something they found online? Perhaps those recruiters might try to walk a mile in someone elses bunny suit.