We've done well to get this far without a debate as to what Squaredle deems to be a valid word, an invalid word, or a bonus word. It doesn't really matter does it. I only get peeved if I swipe what I think to be a perfectly cromulent word that Mr Squaredle considers a bonus word (eg 'torpid' 'umber', 'didact') if I'm struggling to get to the next hint. Except that most of my bonus words are ones found by randomly swiping around the screen in desperation, so that I'd prefer a lower 'in the top n% by bonus words' value than a higher one.
Today's grid was the first one I noticed where US spelling had a bearing.