Exactly. The IRR in investing more into ad platforms for Google is still higher than any other project so they keep investing in it and increasing their ad revenue. Alongside Meta, they have a duopoly (monopoly?) on that market for now so they are just milking it for all its worth.

You don't just build stuff for the sake of it. It has to be a better investment than what you currently have, and Google doesn't have anything better than doubling and tripling down on ads.