I can imagine Google not being very motivated to add a button that removes cruft, including (google) ads. I'd say they did provide a solution in the form of AM

I can imagine Google not being very motivated to add a button that removes cruft, including (google) ads. I'd say they did provide a solution in the form of AMP, which of course is much better for them because at the very least they get to suck in more data (and still display ads!). Of course it's also entirely possible that the Chrome team just hasn't prioritized this feature.