So I finally decided to experiment with the Dad 'n Me framerate. Someone told me once that even though the browser doesn't play Dad 'n Me at the full 30fps, if I set the framerate higher, it would run faster in the browser. That just didn't make any logical sense, since the browser can't even run it at the intended 30fps.
I decided to give it a shot and exported a 45fps version. Low and behold, I think it worked! The game now seems to be running in the 30fps range in my browser.
Go play Dad 'n Me and let me know if you notice the difference!