When World of Warcraft Vanilla launched 15 years ago, most players were playing their first or one of their first MMORPGs. A lot of players were teenagers and excited about entering this epic world. Most players were very nice and you had the feeling your were part of a server, a community, a guild and a real world.
Over the years this feeling has changed. Now when you enter Battle for Azeroth, your server is almost irrelevant, players swap guild more often and the community feeling is worse. Of course this is based on my personal opinion, but I have heard more people share their concern about this topic. I think there are several reasons that the feeling of community in WoW Vanilla was a lot better than in WoW BfA:
The game was new.
Most players in BfA have played at least several expansions. They are not as excited about the game anymore, compared to the first time they played the game. This loss of excitement makes people less involved in the game and therefore engage less with the community.
Making groups is more difficult.
In BfA you can easily form groups for mythics, raids and world quests. You can press several buttons and your group is ready to go. This is very convenient, but it also makes the process of making a group less personal. You are not using social interactions to create a group. The lack of these mechanics in WoW Classic, forces you to interact and it makes you more involved with the other players.
Travel time is longer.
In the original World of Warcraft, it could take you quite a while to get to the entrance of a dungeon. While this might seem annoying from an efficiency perspective, it actually led us to be more involved into your group. Deciding to leave a dungeon group wasn’t something you did lightly and caused the interaction in your party to be better.
Focus on solo play.
In BfA I have been doing several quests with another player, without grouping up with this person. We could both kill the same mobs and get credit for it. There is no need to group up and therefore social interaction is limited or non-existent. In the limited time I have played the Beta of WoW Classic, I have already grouped up more with random people then the last couple of months in BfA.
WoW Classic will have nostalgia.
A lot of people that will play WoW Classic will have some nostalgic feeling towards the original WoW. Being nostalgic makes you appreciate the game more and probably wanting to share this feeling with other people and engage with them.
Leveling in WoW Classic is harder.
It takes you longer to gain experience in WoW Classic. On top of that it is a lot harder to defeat enemies. It is very often necessary or recommended to group up with others. Again, the mechanics force you to interact more.
All these points will most likely lead to WoW Classic having a way better community than WoW BfA. Hopefully this will stick and we will find out we were nostalgic for good reason! The only advise I can give to make WoW Classic a succes is group up and be nice!