I really like studying. Like, my list of things to learn more about
in CS/software engineering/Math alone is probably longer than I'm going to get to before retirement... which, if I'm lucky, will consist in no small part of studying things and working on personal projects. I don't understand people who say they don't want to be immortal, they'd get bored. I can sortof imagine my psyche eventually crushing itself under the weight of its own history but... boredom? Nope. Too much interesting stuff to learn/try, even at the scale of challenge available to us now.
So, trust me when I say I don't object in the slightest to being asked to study and learn things. LeetCode-style problems look like one form of recreation to me.
And yet, I still think this comment is shortsighted because:
* I'd guess a lot of what's on LeetCode isn't exactly untrodden territory for any developer that got their start before 1995.
* Distinguishing oneself can work in the individual case, but it generalizes poorly. Imagine employers and would-be job-seekers alike internalize LeetCode knowledge as a standard distinguishing mark. Like college degrees, distinguishing points often over time become standard expectations. The likely outcome is that about as many devs in their 20s & 30s can brandish the same "distinction" that devs 40+ can and the incentives to prefer youth perform about the same.
Individual efforts to improve ones lot are a good place to start, but they rarely solve systemic problems.