Ortiz is the more skilled and many will back him purely because the dislike for Wilder and the fact that Wilder appears to struggle to throw a punch with textbook form.
However I think Ortiz may have some early success but in the end prove to be a bit too long in the tooth and eventually get caught and put away. I'm not a fan of Wilder but I can see something big landing for him eventually and getting it done, likely in the second half of the fight.