To reword it, leetcode is a barrier to entry for newcomers. It's pure gatekeeping and it says as much when people think they have to 'grind' it to have any prospect of a job.

It teaches you absolutely nothing about the rest of the job, around comms and leadership, which most of the time are more important than your ability to solve puzzles.

It selects for people who want to get in and want to grind.