I just explained when I would use the switches. Whenever it isn’t actively in my hand. If the question was inversely when do I use my phone then. Strictly when I need it, I text someone, I check email, when I need maps fro directions. My screen time is consistently 2-3 hours a day. I would rather have a big brother on my shoulder 3 hours a day than 24 hours a day. If I need to search something truly sensitive, I have other methods and devices for that.
About phone addiction, phones are incredibly addictive because they are never truly off. Kill switches basically lobotomize your phone on the hardware level and I’ve noticed doing that same thing with Faraday bag is very useful for focus. Self disclipne is a finite resource, why use it to something that can be solved by good engineering instead? You can’t tell true phone addicts to just use self disclipne alone, just like you can’t tell alcoholics to use self disclipne alone to stop drinking.