Man you really shouldn't be so hard on yourself. These coding interviews aren't IQ tests. If it's any help, a good recommendation from someone in a company would probably be a stronger signal than a leetcode type question.

My feeling is that getting a job is like dating, a mysterious mix of luck skill chemistry etc, there are some rules but you can follow the rules precisely and still end up losing just because of some odd misfortune. However if you try long enough and put in a solid good faith effort, long enough being unspecified and possibly after you die or go broke, you generally end up with something decent.

That long enough part is the kicker and that terrifies me in every job search (to the extent I have sometimes jumped at the first half decent opportunity, and agreed to salaries below my potential). I find it does help to apply often and everywhere and not be invested in any particular opportunity.

With dating they say every failed relationship is a step toward finding the right one, and I think that same principle applies to job interviews.

Anyways, that’s my two cents

I worked at Facebook for years and did a lot of interviews and the hiring process has inconsistent results for all but the best and worst candidates. The amount of times a candidate was rejected because one iterviewer who had questionable rationale was surprising.