I have been experiencing the same thing you are describing in terms of procrastination/free time being spent in the less productive ways than one wants to or imagines them, as well as productivity being inverse correlated with free time.
I think it is definitely psychological. Probably something to do with subconsciously feeling guilt for not doing what one is "supposed to", so they feel too guilty to embark on something else that's productive or educational (like reading that one textbook they planned for a while). And instead just go "ok, that one educational thing i wanted to do is gonna take a while, and i am already wasting a lot of my free time, so instead i will just check out a few cat videos and then get back to productive stuff". And then it just becomes a positive (aka self-reinforcing) feedback loop that keeps on feeding onto itself.
As for being productive with the least amount of tree time, I can confirm that my best GPA in college was during semesters when i had the heaviest workloads on top of a part-time job. Reminds me a lot of what many parents on HN say in the comments, how they became way more productive in their efforts and focus after having kids (as soon as they get to about 1-2 years old). No experience with that one myself, but seems very similar.
> Probably something to do with subconsciously feeling guilt for not doing what one is "supposed to", so they feel too guilty to embark on something else that's productive
Absolutely. I have found myself in this exact loop (or is it a downward spiral). I cannot give myself "permission" to do what I want in times when I know there's no chance I'll do what I'm "supposed to" anyways. This only makes the guilt worse the next time.
I think it is definitely psychological. Probably something to do with subconsciously feeling guilt for not doing what one is "supposed to", so they feel too guilty to embark on something else that's productive or educational (like reading that one textbook they planned for a while). And instead just go "ok, that one educational thing i wanted to do is gonna take a while, and i am already wasting a lot of my free time, so instead i will just check out a few cat videos and then get back to productive stuff". And then it just becomes a positive (aka self-reinforcing) feedback loop that keeps on feeding onto itself.
As for being productive with the least amount of tree time, I can confirm that my best GPA in college was during semesters when i had the heaviest workloads on top of a part-time job. Reminds me a lot of what many parents on HN say in the comments, how they became way more productive in their efforts and focus after having kids (as soon as they get to about 1-2 years old). No experience with that one myself, but seems very similar.