The huge caveat here is assuming gravity is quantised in the same way as the other forces, gravitons don't need to exist for gravity to exist. This is just the beauty argument of string theory with a new name, it's cool and I love this type of stuff because it's amazingly satisfying, but that's not enough to make it reality.

Don't get me wrong, this is still useful work but I kinda hate the way quanta reports on a lot of physics...