I got my 100th dislike yesterday!
Honestly, I just treat them like likes, it's engagement, someone cared enough to leave their mark
YouTube doesn't care whether a thumb is pointing up or down, as long as there is one, and that's how I feel too
Sometimes you get a trail at once, and that's just a troll giving me some views and clearly upset/jealous/angry for whatever reason, which ultimately reflects more on then than me/my content.
And that is what I do to process dislikes.
Of course, if there was an unusual surge then maybe I'd be concerned if I'd accidentally said something controversial but otherwise, I think dislikes are just a reality of videos that get viewed, and in that regard, I welcome them