What works for me is removing the antecedent completely by charging my phone in another room at night.
Now the battle is easier: Decide once a day to put it there, and track how many days you succeed.
For me that's a lot easier than having it in my pocket, where the Internet is always a couple lazy taps away. Now I at least have to walk to it if I want it, and that often "breaks the spell."
I finish work and chores hours earlier when my phone is charging in another room, without consciously doing anything else differently.
It really makes me want a 1980s-style cellphone with no screen and big physical buttons.
You see, I've actually had some success with using Blocksite on my phone and blackholing things on my laptop by editing /etc/hosts. Of course if you have the access to put these filters in-place then you'll have the access to remove them, but the time it takes to fire up the blocker on my phone and disable it or to pop open a shell and type "mv /etc/hosts /etc/hosts.bak" is time enough for me to go "Am I actually accessing this because I care about some particular piece of content or am I just trying to plop myself into the dopameme stream?" It's not about 100% physically preventing myself from accessing these sites. It's about interrupting the flow. I used to have a problem where I'd be doomscrolling FB or TikTok in particular, realize that I haven't had any actual fun in about half an hour, close the app and exit the loop for a second, start looking for something else to do and then compulsively open the app again and start doomscrolling. Getting rid of the apps and having the web version default to being unavailable has made it so that I can still do the social part of social media with real people who send me content that I actually like and want, but I can't do the completely antisocial part of social media where robots send me content designed to piss me off and frighten me so that I interact with them and their masters get money.
I think there's one common element between our two approaches though: intentionality. Whether it's opening up a second app and disabling it, or walking into the other room to physically pick your phone up, there's an intervening step that allows us the space in which to go "Do I actually want this?"