Data Engineers Don't Need DSA. So Why Do Interviews Still Test It?

I did somewhere around 20 interview loops during my last job search. Phone screens, take-homes, onsites, "culture chats" that were secretly technical screens. At one company I did eight rounds, was told I passed, was told the offer was sent, it was never sent, then a new recruiter said I'd declined the offer I never saw. I did four more rounds. Passed again. Headcount was closed. Through all of that, you know what never once came up on the actual job? Inverting a binary tree. This debate isn't n