You're thinking of the novelty of an element of the product on a far larger scale than the market did. Celeste has novelty to it in some of the places I mentioned before, so I won't concede it has no novelty on the larger scale, but most importantly, it was novel in 2017-2018.
Marketing began it's popularity, word of mouth carried it to the finish line, and why would you share a game if it wasn't good?