Something that worked for me: I bought an Onyx Boox Note, which runs most Android apps. I installed all of my news and social apps on that, and uninstalled them from my phone. When I want to consume content for entertainment, I use that. The e ink screen adds enough friction and takes away some of the stimulation, so it's far less addictive. My phone use has dropped to about 1 hour a day, just for necessary messaging, banks, maps, etc. My e ink tablet usage is probably 2 hours a day or less.
This doesn't really prevent re-installing scroller apps. But if your phone is in your hand less often, and you have another way to check those apps from time to time, you won't have as much temptation to fight.
I also leave my phone around the house instead of in my pocket. I put it on the table, or leave it on a shelf, etc, and forget about it. I also recommend going for a walk every once in awhile and leaving your phone at home.