Exactly there's no way a non incarnate will ever surpass the power of incarnates(who rely on power ups), except with ass pull after asz pull or plain bad writing.
Realistically, it's not likely for him to surpass both incarnates considering the Jougan doesn't exactly grant the user tremendous reserves of chakra.
Some of the strongest Naruto characters needed an outside/innate/metempsychosis source of chakra to become stronger.
Madara, Sasuke were blessed with Indra's chakra.
Naruto, Hashirama were blessed with Ashura's chakra.
Hagoromo and Hamura had Kaguya dispersed chakra.
Kaguya's chakra came directly from the god-tree.
Momoshiki's chakra came from capsules.
Boruto's chakra currently is rather average, there's a no sign he's going to get a huge amount of chakra in the near future. Unless that changes, I don't see how he surpasses them. Perhaps his Jougan is key to a dimension filled with raw chakra.