> And no one bothers to look at my portfolio when I've been contacted to apply for engineering positions.

I think the root cause of all interview issues is that interviewers aren't incentivized to care. You're never going to get promoted or even a good performance review for reading a candidate's code or ask them meaningful questions. On the other hand, it takes little effort to pick a couple algo questions and use them for everybody, and they still provide some meaningful signal. With alternative interview methods, apathetic interviewers will just rely on their intuition, which is how a "good ole boy's club" is formed.