But even if not, you get asked whether to turn on Siri, whether to send telemetry, whether to sign away your rights, etc., all of which are consequential but prompts are massaged in a way where it's nice and easy for the user to answer a certain way without having a clue. Makes me think user comprehension isn't even a problem.
Where I suspect the problem lies is that it will not fly to make it seem like US-based CA's are more trustworthy just because the majority of sites roll up to them. Then you'll need to do some non-country-specific human tiering, and who's the judge of that?
So what happens to americans visiting french sites?
[Do Not Trust], [Trust Once], [Trust Forever]"
The country comparison doesn't do much either, because there isn't a good guarantee that they'll correspond. Some guy posted a repo to distrust every CA except the top 30, and that has a bunch of weird examples, like a bunch of russian sites being signed by a Greek CA. Not to mention some of the biggest sites use CAs that don't correspond with their country of origin. GlobalSign is Belgian for instance. Guess how many of their customers aren't Belgian?
You can add other options too, "Trust for 30 days" or something. I wish SSH known hosts has an auto-expunge.