Unfortunately, the only real constrain for it to not continue to exist would be to cost some people their political career due to media/public backlash and such.
No, you've misunderstood that. The article mentions that he's been stopped previously, and asked for his passwords, and has declined before without being arrested.
So maybe that low arrest rate is a glimmer of hope: they could be arresting many more people.
It still sucks, and it clearly needs reform which is unlikely under current or future governments.
The UK is weirdly comfortable with massive levels of surveillance.
Maybe, I mean I don't know about "most voters" to be honest. I certainly feel like we're defeated and will be walked all over for the rest of our sad existence