I think I’ve already said this before but I don’t watch very much action and I don’t think there are many non-action anime that would qualify for this. I couldn’t even think of a single fight scene I remembered watching recently at the start.
Ultimately I had to choose Saitama vs Genos in One Punch Man. Compared to other fight scenes where a couple characters just punch each other until they can’t anymore, I guess if just seems so over the top and ridiculous. I guess the whole of One Punch Man is but this fight just particularly stands out for some reason.