I don't think this will happen, at least not for every pro out there. The reason why every pro moved from voobly to DE was that the money was there and they were still gona rule in the new game. There's no guarantee for Viper, Hera, Yo or any other top 10 player to continue being top 10 player in Aoe4. Yes, they will be really good. But really good don't win tournamentsThis whole thread will look really silly when the whole pro/streaming scene moves to aoe4 forever because that's where the money will be.
Remember when everybody instantly moved to DE despite the cuman steppe lancer meta, the melee pathing and BF in 1v1?