This effort by Google, at its worst possible implementation, could break a huge number of "required" websites for users. As others have pointed out in this thread, the users who will be impeded are likely already at a disadvantage[1]. This just reinforces that, especially if everyone starts adopting this given how it is "free" for businesses/organizations.
A convenient side effect? Google gets more information about us and encourages us to view more ads.
[1] Someone mentioned smaller villages in India. The GOV.UK reference talks about users with disability. One could also imagine shared locations like public library, whose users may not have direct access to the internet.