Well its not about the quantity its about the quality of the wins, isn‘t it?
Since the two race in the modern cycling era, I see no reason why the two shouldn't be compared and Pogačar's palmares is already really close to Sagan's after just 4 years as a pro.
Sagan had a career of paradoxes. His three consecutive World titles were legendary and the 7 green jersies at the Tour was also something amazing but I just find a bit disappointing than he never wore the yellow jersey in the Tour and more important than that only won two monuments, even though he still has a small chance of finally winning MSR this year (should have tried LBL in his early years too). But I think he correctly recognised that his best days on the road are over and want to have some fun in the MTB. Wishing him all the best.
He wore yellow in both 2016 and 2018.