The game when Walton played was very different. A lot of it was focused on the fast break, and Walton's best passing attribute (throwing outlet passes) wasn't kept track by statistics. He never was asked to ball-handle or shoot, or play make in the half-court the way Jokic is, so it's hard to compare the two. He was a much, much better defender, arguably the best defender in the league at his peak, although of course his role was very different (protect the rim, rarely had to come out and defend the pick and roll).
Jokic is much more similar to Bird, I think. If Bird played today he'd handle the ball a lot more and his passing would probably have an even bigger impact on the game than it did back then. Jokic is bigger than Bird, Bird maybe a smidge more agile and Bird is a better outside shooter. But this is what Bird would look like today; and Jokic really should have won 3 straight MVPs like Bird did.