Part of the problem is people are just burned out on wow period, BFA is mediocre at best which has turned a lot of people towards classic, not because of how wonderful classic was but because were so desperate to play something fun and interesting we are resorting to 15 year old content. Don't get me wrong I am not bashing classic I was in the original beta and leveled a 40 paly during that beta and I have been playing wow ever since but lets not kid ourselves here if this were Wrath, TBC or even Legion the numbers on classic wouldn't even be remotely this high because those expansions were extremely good and kept people happy, BFA is a snorefest and people are bored with Legion 2.0.
This is my question to blizzard, have you given up on BFA to the point that you would release old content that actually pulls players from your newest current content? It seems to me that blizz has realized BFA at best after 1 year in is failure and yes failure will be interpreted in different ways by different people, but imo if an expansion is not compared to the top 3 like Wrath, TBC and Legion than its simply not very good and just another let down in the eyes of the wow player base. Is it the worst expansion? No absolutely not imo Cata and WoD were both worse some would put MoP in there as well, but everyone's opinions vary.
I have cancelled my sub on BFA twice now, its boring, its nothing new compared to Legion and I for one am disappointed over all with BFA, not all of it but the majority of it. I will be moving on to Ghost Recon in October and hopefully that will keep me busy for a few months. I really hope blizzard gets off their asses for the next expansion because this cycle of one good and one or two bad expansions is getting a bit old for me but as we all know to well it wont stop me or anyone else from buying it lmao.