I am not denying your argument, however, as
@Kurozumi Wiwi implied - Loki could be an anomaly in the crew like Oden was for Roger's pirates.
And, Zoro and Sanji will surpass him sooner or later so a temporary diversion for an arc or two won't make much of a change anyway especially when we are nearing the end and Loki might have some narrative significance and alignment of goals.
End game imu?
End game Teach
Nah
Bet has to be about Elbaph only because it will give conclusion to the bet sooner. No point in holding the bet until the end when hardly anyone would care or remember about it