Earlier quoted context omitted.
> A side-effect of a Chromium-only web is that it gives the Chrome team at Google less incentive to invest in the web platform. It used to be a way to differentiate Chrome from other browsers. Now-a-days that is no longer the case. That's what happened with Internet Explorer but the reason Microsoft was perfectly happy to stall the development of the web once it took over the browser market was because it didn't real…
Yes they can act unilaterally and with Chrome OS and many popular web apps they do have incentive to care about the web. But will that translate to the Chrome organization caring? It doesn’t make Chrome a more attractive browser to users than other browsers also built on Chromium.
If they decide to add new amp integration or similar features, for example, that can give them more control of the Internet even if you are using those features through Edge rather than Chrome.
Seeing Google's goal as getting everyone on Chrome is missing the point: it's just as good from their perspective to simply have everyone using chromium based browsers.