So almost every GDPR cookie consent banner out there has a section for “legitimate interest” cookies that they can leave on by default and you will inadvertently accept even if you choose “Reject all” unless you go to the detailed settings and disabled those too.
Some of them have dozens of legitimate-interest cookies.
I read some articles about what they are and why it is allowed to keep them on by default, but they were very vague. So can someone explain it to me like I am five?
Just a reminder that there’s never such a thing as “a loophole”. What there is is a carefully-worded, innocuous-sounding phrase that some corporation “helpfully” got added to a law or regulation (usually “for clarity”), and which the corporation already plans to mis-use in a given way should the appropriate circumstances arise (and in contradiction of all “we should never do that!” protestations they might make prior to the law or regulation taking effect).
Again, there is no such thing as “a loophole”.