He is not a top 20 point guard at all.
Westbrook, Curry, Irving, Walker, Thomas, Bledsoe, Conley, Schroder, Lowry, Lillard, Dragic, Wall, Paul, Harden, Beverley, Hill, Rubio, Holiday, Teague are all WAY better than him. That's already 19 players. Then you have players like Williams, Rose etc. who are fading but still better and a host of not great but decent enough players like Dellavedova, Barea or Payton who are better too, not to mention the significant number of upcoming young talents like Fox, Smith, Ball, Fultz and Ntilikina who will also be preferred to Jennings 10 times out of 10.