Yes, this is a very stupid thing to do. However, police in UK or the US, do not shoot people for just being in possession of a weapon, whether it is legal or illegal or real or fake.
Yes, this is going to get you stopped and may even cause them to draw weapons as the ask you to lay down on the ground. Which is what happened here. He didn't get shot because as stupid as he was, he was not so stupid as to resist the police.
The BS narrative that certain constituencies are making is that police shoot first and ask questions later.
In almost all of the recent shootings, the victim, refused to comply with police instructions and resisted arrest.
I don't know where people got the idea that a police office has to justify to you why you are being arrested before you comply. If people keep thinking that, then we will keep having situations like we just had. In this most recent situation, I'm not saying the cops were in any way justified, from what I saw, lethal force was not justified, but even racist cops aren't going to shoot someone who complies with their instructions.