time is your most valuable resource, and you dont even know how much of it you have left, so you definitely should spend it wisely. however the relevant question isnt if its a productive use of your time, as its not realistic to expect yourself to be productive for 16 hours a day. you also need downtime. preferably multiple hours of it per day, and some days where its almost entirely downtime. the question becomes is it enjoyable. if its productive, its a good use of your time unless you have more pressing, thus far more productive tasks you should tackle first. if its not productive, then its still a good use of your time if its enjoyable or meaningful to you. the problem is when you find your self repeatedly spending lots of time on something that is neither productive, meaningful, nor enjoyable. thats self-destructive behavior, thats a waste of time. and social media, of course, is a waste of time.