This is one of the most detailed and balanced articles I have read so far on the topic. However, like every other one I've read, it omits one very important clarification about 'Web Environment Integrity':
It is not part of the Web. This is exclusively a Google draft for a Google Chrome feature, and whilst Google is a member of the World Wide Web Consortium (W3C), they are not doing this as a member. I don't believe such a proposal would get even as far as a working group charter, given how limited it is to Google's interests. The only reason that it's a threat to the Web is because of their overwhelming market dominance, which is approaching a monopoly already.
I fear that the prominent use of the term 'Web' in this kind of document is tarnishing the reputation of the W3C, who have a solid process[1] to avoid pursuing these short term interests when they come with the risk of long term damage to the openness of the Web.