The HL3 memes don't even seem fair to use anymore. I don't even want to un-seriously make joke fun of them at this point. They are just genuinely doing so much for the community.
But overall Valve just seems straightforwardly less shitty towards the consumer than other major companies in their space, by a long shot.
Look at all the horror stories about businesses that were bought by PE firms; those are all privately held too.
In that regard "bought by PE firm" (or most any prospective buyer, really) is functionally equivalent to an IPO. Selling out is, in fact, selling out.
It's not just functionally equivalent to an IPO... it's an IPO if all the buying new shareholders were sociopaths.
(Yes, there are the PE companies who run businesses better like Berkshire, but that's far from the most common type of PE)