This headline is pretty misleading. It makes it sound like they're giving access without the user's consent, but based on some other articles I could find (eg:

This headline is pretty misleading. It makes it sound like they're giving access without the user's consent, but based on some other articles I could find (eg: https://uk.mobile.reuters.com/article/amp/idUKKCN1M02P9 https://uk.mobile.reuters.com/article/amp/idUKKCN1M02P9) it looks like what's really going on is that users can give access to third party Gmail add-ons. Those add-ons in turn are capable of giving access to someone else, though it is against Google's rules to do so without the user's consent. This seems a bit like claiming "Google confirms it lets other users read your email" because the ability to forward (or even copy and paste) exists.