If you don't see the issue with Google enabling putting up paywalls, but only on sites that are showing ads that belong to them or to companies that made a deal

If you don't see the issue with Google enabling putting up paywalls, but only on sites that are showing ads that belong to them or to companies that made a deal with them, while blocking ads on sites that don't do Google's bidding, I'm not sure what to tell you. Note that they are not being public with their list of sites that they will block ads on and reason why; nothing prevents them from putting sites on that list for any arbitrary reason they want.