Maybe that's just confirmation bias though? Ie the PE-owned well-run companies don't make the news?

I know one example: NXP Semiconductors. Got spun out of Philips, along with all the Philips cultural baggage (which means high bureaucracy and low productivity). A PE firm bought it, kept yelling about the bottom line for years on end, and everybody started cutting away waste, ineffective people (the "human furniture") got fired, prestige projects that had no economic value got killed, and they started shipping.

I'm sure it's not all been roses and sunshine but last I checked, NXP is a better company than when they were a part of Philips.