Stupid things like brexit was put to a vote, but really important things such as age verification and mass surveillance are never put to any vote.
But Brexit was a vote, by the people. Yes, the pro-leave campaign lied to no ends, but people still made a choice on their own and the majority for leave was quite slim.
This is very different to age sniffing here. Age sniffing is not being queried via public votum - lobbyists push it through without any resistance. It's amazing how this works.
In what way was Brexit a stupid thing? It was an extemely important decision, directly affecting everybody's life. If asking people about anything then isn't that what it should be? You might not like the outcome (I don't) but I consider the question of Brexit important.