I don’t doubt that and think Remco has more talent and a vastly higher ceiling than Johanneson. I know you will also agree with the point that L’Avenir will no longer be as strong a reference point whilst riders are skipping it despite still having 4 years of eligibility to ride it. I was impressed by his climbing and do think his pro career will be more successful than Foss who has already outperformed my expectations with that 9th in the Giro.Johanneson is actually older than Evenepoel, Skjelmose, Van Wilder, Arensman... He pretty much followed the example of his countryman Foss: take the big U23 win in your final year against b-tier opposition and guys 3 years younger than you, because all the others have already turned pro by then. I'd wait a bit before expecting a clash.
The other thing to note in seeing it as a clash is the difference between priorities like Remco/Ion Izagirre in Itzulia where it was an absolutely key season goal for 1 rider and a prep race for the other rider. The absolute peak levels are different but being at different stages of their form peaks will act as a balancing force.