The problem is, for every person like you, there's a person like me that actually likes those types of challenges and wouldn't actually mind being thrown into that type of gauntlet. My years of experience be damned.
One self-driving car start-up in SV wanted me to solve a long-standing research problem (Deep Learning) as their week-long take home test. Thanks, but when I do, you can license my tech, I will gladly make it available to you for $.
During my professional time I write software to make money. During my free time I write software to make money. As an aging software engineer algorithmic questions just screen for how much time you're willing to put into an interviewing. GitHub screens for how much of a sucker you are.