I've taken a lot of shitty interviews. I have also interviewed many devs.
Testing a candidate in one hour is really hard.
CV's can be very deceiving. What I look for is folks who are good coders and good communicators. I don't care about culture fit. Our team is diverse from 50 year Olds, 19 year Olds, males females, black, white, brown etc.
Having a github profile with interesting projects is a boon. Even better if you've contributed to some meaningful open-source projects. This is great because it gives lots of data. The issues you file, the commits, comments and code give good insights about you. Much more than a one page CV.
I use the same question on every candidate and evaluate them.
I allow my candidates to use google/Bing, chrome console, whatever resources they would usually use in day to day work.
I look for understanding of basic data structures like maps, sets and techniques like recursion. I also give a ton of hints to guide in the right path. I can only help though if the the candidate wants help. Some candidates really don't get the hints even after multiple repeats.
Some candidates just dive into code and then get stuck. They confuse them selves.
The best candidates are the ones who ask lots of clarifications at the start, they break down the problem into little pieces without writing a single line of code. They emulate a computer and trace the steps in an abstract manner. They think like "to solve Z, I need A then do B and C and D." They then slowly write code for the little steps.
I love candidates who can give me a deep dive into a subject they are an expert on. I get to learn a ton on random things. Also gives insight on what makes them tick.
Don't give up. Please keep on trying. Feel free to PM me for any help. I really want you to succeed.