It's been brought up a few times on HN recently, but I think it's worth bringing up again - Imposter Syndrome is rampant in our field. It's the reason a lot of people drop out or don't even get into it. You're far from the only person who feels this way.

Interviews and conversations online may lead you to feel like you need to beat yourself into reading books on operating systems or some other specific sub-field, but a sincere interest in things like garbage collection isn't the only path to success. Algorithms comes up a lot because it's easier to filter for people who know the topic well, but those people have gaps in their abilities, too. Those topics aren't more important than things like domain knowledge or writing maintainable code, they just aren't always as easy to recognize, test for, or brag about.

Sure it's good to learn them, but learn them when you have some motivation to - start writing a game and then read about path-finding. Learn RegEx out of an interest in shortening some code at work. Turning learning into hard work by forcing yourself to learn about things that don't interest you is just going to make learning more difficult. What's important is just that you learn something - so relax and do something fun.