I don’t know how I feel about this personally. On the one hand, I feel like this is a privacy win for those who want it: no watch history means no algorithmic recommendations and (presumably) less data collection for those users. On the other hand, I personally really enjoy the recommendations that YouTube makes for me. Maybe it is the wide variety of content that I watch, but I’m honestly very pleased with the recommendations that YouTube provides. That being said, I feel like the opt-in to algorithmic recommendations is a good thing overall, however I am personally going to leave my watch history enabled.