That is a ligit link!
But, if you don't be believe me, go to the site: https://www.change.org
Or Google it, if you don't want to click on "that" link.
Then copy/past,
p/masahiro-sakurai-nintendo-add-l-shape-tetris-to-your-next-super-smash-bros-game
into the URL, if that makes you feel safer about signing it.