It seems you are confusing strictly necessary cookies with legitimate interest cookies, which are different things: https://kbin.social/m/[email protected]/t/466192/-/comment/2427882
It would help to clarify in the post that you’re interested in the legal aspects for the EU under the GDPR.
I had added the #GDPR tag to the question and, as far as I know, GDPR is the only regulation that requires a cookie consent banner and mentions legitimate interest cookies, but I may be wrong on that as I don't know all the regulations around the world 😃 (and California tends to follow EU's stances on these matters, so I wouldn't be surprised if they were baking something similar to the GDPR if they don't have it yet).
But yeah, you are right, people from many different places around the world could be reading the question, so I must have been clear that this is specific to some local regulation. I edited the post.
OK, so all the explanations I saw were vague because the law itself was vague. That looks quite like a loophole to have passed!