The main issue is that no-one in past, be it movie, music, or gaming industry, had the control which Google has with the web.
Web is 90% Chromium, Email is 60+% Gmail, Android is 70+% mobile worldwide, and Google already provides a lot of things like Google login, oAuth, etc. for free.
This means for a web dev, making a website WEI compatible shouldn’t be much of a hassle, and if they protest, Google can totally twist their arms to get us way.
WEI is dangerous because who’s behind it, not because what it is.