Surprisingly, the one thing that occasionally manages to distract me is this very forum - Hacker News! :) If I observe myself spending too much time on Hacker News, I block it at the /etc/hosts level. I have a little shell script to point news.ycombinator.com to 127.0.0.1 when I don't want to be browsing HN. HN provides a nifty solution of its own too in the form of the "noprocrast" setting in your HN profile page. If you haven't checked it out yet, it is definitely worth considering.
Apart from that, I think I've been able to escape the traps of modern social media. Also, I still depend quite a bit on physical textbooks, a rollerball pen, and a stack of plain A4 paper for most of my learning, thinking, and exploration activities. This routine has helped me to stay away from modern social media too. So, fortunately, I still have the luxury of boredom in my life which I find to be an essential ingredient for digesting new knowledge as well as finding creative solutions to difficult problems. I've found that letting my mind wander aimlessly sometimes leads to new insights when I least expect them. I think it also helps with creativity and reflection, in general, which is likely a nice bonus too.