Back in the super old days of blogging, like 2004 days, we use to love pingback technology in blogs because it was an automated way to get a link from a relevant blog post on someone else's blog post and get some attention. But quickly it because super spammy. So when Gary Illyes of Google said on Reddit "very very likely those pingbacks are marked worthless (meaning they're ignored) on Google's end" I would trust that.
If you want a more official definition of a pingback, see Wikipedia. But I think I described it okay above.
In short, the person who posted on Reddit was afraid that those links will end up hurting the site in Google Search. He said that one site "resulted in over 2,200 no-follow backlinks from one pingback, and as a small blog this is the vast majority of my backlinks. They all have the same anchor text, as they’re duplicates of the same thing." He wanted to know if he "should I try to get the pingback removed, or is it not likely to be an issue?And if they don’t respond to me asking them to remove it, what options do I have?"
Gary Illyes from Google said he should not worry and that Google is probably ignoring those links anyway. Gary wrote "is this causing problems or you just need a peace of mind? I'm asking because it's very very likely those pingbacks are marked worthless (meaning they're ignored) on Google's end, so it's highly unlikely they'll cause you troubles."
Yes, Google has said many many times that it is good at ignoring links that it does not trust or finds spammy. Here is one more time a Google rep has said this.
Forum discussion at Reddit.