Chrome is similar to other apps like X, Instagram, or YouTube. You click on the app. You are given a way to discover content and ads are shown along side that content. When you click on a site / post there can also be ads. Maximizing engagement on the web, means people will discover more content, which means more ads can be displayed.
>AMP
Unlike the other platforms I mentioned the web hosts content using 3rd party tech stacks and server which means that the user experience can be variable. AMP allows Google to provide a more consistent experience. It was optional and served to provide a better user experience for the users of the web.
>Ad-blocking prohibition
Google Search and Chrome have not prohibited ad blockers.