I'm surprised you're getting downvoted, because this seems like a valid criticism and was the first to pop into my head as well.

How is this not anti-competitive? Google is favoring the ranking of sites that use its own tech. According to the AMP docs on third-party components [0], only 5 ad networks are supported, most of them Google-owned.

[0] https://www.ampproject.org/docs/guides/third_party_component...