Should supermarkets just sell alcohol to 10 year olds?
I think there are plenty of places where age gating makes sense as a concept, it really is mainly the data security that's an issue. The other is that it should be somewhat circumventable, which I think mainly requires it not being tied to identity (so much like you could get someone older to buy you alcohol you could get someone else to verify your age).
What I think is bad is age gating social media instead of doing something about how harmful it is because clearly adults are not immune and all that does is make it harder for children to get important information.
It's interpretable that way because it's the only sensible meaning the sentence could have, but grammatically it's pretty much nonsense (the only grammatically correct interpretation I can parse from that is that the speaker owns less people than have been to berlin). It's purely context inference, it could say "more people berlin than I" and you can come up with the same interpretation.
Fwiw I wouldn't reach that one at all, best I could come up with is "I am one person, more than one person has been to berlin, so more people have been to berlin than just me".
It undoubtedly is nonsense.