It's a prerequisite, but so is breathing. It's necessary but not sufficient.
The bar I like to use is pretty simple: do you know who represents you in Congress (I am American so this is my bias, but substitute your country's equivalent if there is one)? As in, your state's two Senators and your district's Representative? If not, you probably don't vote or don't pay attention when you do, and you've definitely never called your Congresspeople to complain about their votes, so you probably don't really care that much about whatever it is you say you care about, since you haven't done the easiest thing you can do to make a change.
It's not perfect, and no criteria will be, but there are tons of people who can rattle off "executive, legislative, judiciary" who nevertheless don't know ball.
This particular test might be reasonable, but at some point you're just filtering out anyone who's not in your bubble, which is a problem when your beliefs are extreme because your bubble is tiny.
Imagine a Marxist who refuses to discuss economics with anyone who can't explain dialectic materialism or enclosure.
> and you've definitely never called your Congresspeople to complain about their votes
Or, you know, you haven't lived at the same address for twenty years. In your imagined world where every single citizen either has something so pressing to call their representatives about or is just ignorant, you're still basically filtering out everybody who moved for a job/college/SO/whatever recently. I guess in your mind it's only fitting that they're disqualified from having an opinion? For reference about 12% of Americans change residence each year.