The RankHero / Nohatseo network got hit, and most of the sites using it got hit along with it.
Yeah, the network of mine for an agency client got pretty much mostly deindexed. I'm not surprised, way too much volume per site. But while it worked both he and I made good money.
My own personal network is 100% completely fine, because I'm careful as fuck with that shit.
Regardless, this is to be expected and which is why I'm very happy with my past decision to diversify beyond just doing SEO related stuff.
Diversication is defnitely important. Google is too unpredictable to have it as your only money source. I do believe that properly done PBN Networks won't get hit, none we have made that was done carefully ever has, that said, you never know what Google might come up with next time...
Out of interest, when you said your client's PBN had too much volume, what did you mean with that exactly? Too many outgoing links?