I mean, just google what a Ulez camera is, man. It’s to enforce a low-emissions zone, so that cars don’t kill people with air pollution. It’s an expansion of the already successful low and ultra-low emissions zones in London.
The explosion didn’t hurt anyone but that was pure luck. You cannot safely blow something up on a public road. Anyone who’d been walking, cycling or driving by at the wrong moment could’ve been seriously injured or killed. Again, this is obvious.
And, yes, anyone who responds to a public health policy with explosives is an extremist.