Interesting you raise this as I’ve been wondering the same myself [for indicating reaction/s to a post].
For instance, I’ve thought for a while now that I’d sometimes like to be able to react with a smiling-laughing face for some of the wit & humour one finds on here. And of course a drooling-face for @robertd dishes [not a serious suggestion!]
Having access to just the single emoji to express oneself does seem a bit more limiting than things could be.
But neither IMO do we want a zillion different ones available, I don’t think. I’m talking say 3 different ones to enable different reactions of agree / like / laugh.