it all stinks so much. He calls it "opt-in" but the official description of that opt-in is:
If you try to use Proton Scribe, you will be prompted to chose between local and server-side. So, technically, it's not active until you decide how, and if, you want to use it.
as you can see here: https://mastodon.social/@protonprivacy/112807462045101580
there is opt-in and then there is dangling an expired hotdog