I don't like leetcode either, beyond some very simple problems to demonstrate basic proficiency[0], but if you're going to force poor junior developers to do them, it's only fair that seniors suffer the same process. If it's only an expectation for junior developers then it's just an advanced form of hazing.

[0] on the level of "here's a list of strings that are names in Lastname, Firstname format, turn them into a list of Firstname Lastname", or something dead simple that's designed to definitively rule candidates out