The fact that you are able to pick your own time to get distracted makes all the difference. I read HN when I'm blocked on something, waiting on a compile, on the loo, on a coffee break. The costs of context switching in these cases is very low compared to when I'm deep into debugging or writing code.

I choose when to open HN. It might be more often than is ideal, but it's not mid-thought.

HN feels like a distraction, but i find that when i don't have some sort of distraction i'm less productive. if i'm deep into solving some problem i don't have any motivation to check HN or other time wasters.

but without some way to distract myself in small increments when i need a break, i end up "focusing" on unimportant tasks that aren't material to the actual task i need to complete, which end up wasting more of my time than a couple minutes of scrolling through HN or twitter.

the problem isn't the wasted time, it's the interruption while you're trying to focus. there's nothing wrong with taking a break from focusing.

HN has a few features which might help:

https://news.ycombinator.com/item?id=814695

I use SelfControl on Mac to block sites for deep work: https://selfcontrolapp.com