I've had good results recently by deleting all my social media apps from my phone, BUT allowing myself to use them through Mobile Safari. And I did not bookmark them; e.g. for Instagram I type "in" and then Enter.

This gives me some friction, without having to go cold turkey. All the popular social media sites have mobile websites that are "good enough", but slightly clunkier than the apps, and also they can't send me notifications.

My phone screentime per day has dropped by about 1/3rd.