I hear what you're saying.

But I would argue that the Cornoation is an important public ceremony / event with every right to go ahead.

It's the same as when a foreign head of state visits and the police cordon off the roads for security.

In my view, this is different to pressure or protest groups disrupting traffic or public events.

If President Biden visits the UK, people should not be able to stop his going about a state visit. But they should be allowed to protest with banners and so on if they so wish.