Ad blockers are basically about blocking ads. Yt-dlp has also uses whose main purpose is not about blocking ads.

In some reguards I would say it is. Yt-dlp terminates my need for an adblocker for the lifetime of the videos I download, something chrome no longer does on a per-view basis and these days not as easily. It also blocks the YouTube algorithm suggestions, which in my eyes are an advertisement too.

it's a nice side-effect though.