The Tour de France winner just turned 21.
There's really nothing to say that is negative about Jakob Ingebrigtsen except that he has not yet broken world records or won World or Olympic medals. But then at a legitimate and known 19 years old, he ran 3:28.68, 4:50.04, and 7:27.05, and that is awfully good, in the top ten athletes all-time in three events already. He doesn't have to get that much better to start challenging for the top spots on the podium and possibly wr's as well, and his father has really not tried to peak him yet with loads of speedwork, just a very gradual progression based on physiological parameters.