Google and Facebook recruiters told everyone at my university they expected people to spend 2-3 months of several hours a day leetcode type practice before applying. This was said in a panel type "how to get a job at FAANG" seminar for graduating seniors, with actual Google/FB SWEs present, and all nodding in agreement that this is the norm.
Maybe also quite a few lost innovative startups, which might've been spun out of students making things they want to make, rather than grinding just to prepare for interview rituals.
But there seems to be a large societal opportunity cost to everyone spending several months practicing doing that on a whiteboard, specifically for job interviews.
A gambling addiction is also something you get from (in)appropriate learning experiences.. I think Nordvig's view of programming and materials that fit a longer view of learning good style are likely to work against getting a job in this climate. You are more or less demonstrating your willingness to embrace the anti-patterns a company holds dear to the point that you could be stuck with them without even being considered for the job.
That sounds terrifying.