This is correct as of BfA, however, pre-BFA PvP and PvE servers were seperated, meaning that the realms that had a high PvP population before BfA still have that population now even with the removal of specific server types.
I believe that Ravencrest and Sylvanas were both high-population PvP realms prior to BFA’s release, so I would reccomend those servers over Argent Dawn given how most roleplayers don’t PvP and vice-versa. They are two very different aspects of the game that don’t necessarily share an audience.