I have something similar except that it's permanent and only in software (although I love the idea of a red button). I use NextDNS with a huge list of blocked websites. I set NextDNS as my dns server on windows and android so they're blocked on my laptop and phone.

To use one, I have to go to next dns and enable it, then when I'm finished I disable it again. I find this is mostly enough to make my usage mindful.