It should be telling that there are a number of, usually for-profit, resources for prepping for just the interview process:
* leetcode
* Cracking the Coding Interview
* Elements of Programing Interviews
* Interview Kickstart, which costs like $5500, is a bootcamp just for passing interviews
* educative.io
* algoexpert.io
That being said, I might just play along with the DS / Algo interview game. Having an interview process that is artificially arduous and way outside the expectations of the job duties means that the job market will stay artificially inflated on the demand side. Hiring leetcode monkeys who can barely deploy and manage k8s cluster on AWS means the demand for my skills will be more valuable than if the interview process actually worked. I can complain all day to my bosses about how hard it is to hire (its not that hard) and meanwhile rip their HR budget to shreds when I threaten to leave unless I get paid more (I've done that before, I recently got a promotion and 50% raise on base alone).
So yeah, I'll gatekeep as long as others play too. I hate the game, but I will play it to my advantage.