Mori Jin and Goku are both characters based on the famous journey story from ages ago. It only makes sense that they should fight. As powerful as Jin is with his cool feat of beating 200 quadrillion planet busters in a single shot, he’s not going to do much to Goku. Goku is still faster and stronger. There are very few opponents who can take Goku down and Jin isn’t one of them. He still has chances to get more powerful but I don’t love his odds of surpassing Goku. Goku wins.