Its mainly the scarcity of classic servers, if you look now the ONLY options are mouse server or europa (ru) for a classic pvp server
1 there are no admins willing to open classic
2 there is no free public classic project that is plug and play
3 the hyperbolic amounts of votes and players makes you want to join the crowd
Pandora in reality only has about 200 on during peak hours
Lionna maybe 150
Europa during a good season had about 700 real on, since it was so crowded in the tiny farm zones
Mouse had success on lionna since it was the first 7s pvp server. People wanted to experience the new update, and it has the advantage of being the 'new thing.' It will be the same when they will be the first western pvp server with secret of empire update. Although i personally thought antharas was the last real classic, there are elements from both new updates which fills the voids in antharas