One of the funniest things I've seen since the WoW beta started is Asmongold. Literally only a few weeks ago he was making some videos where he talks about how many years of his life he spent sat in a chair doing 10+ hours a day on WoW and it had consumed him and other aspects of his life and personality suffered and despite acknowledging that and talking about it, the moment WoW classic beta came out, he is back in the chair for 14 hours a day, sat in the auction house with music playing on the stream, knocking back fizzy drinks one after the other, its literally like he has regressed 15 years and hasn't gone forward in life at all
I think a lot of people will play classic and temper it compared to how they played it when they were young, but for someone like Asmongold it will consume him again and goodness knows what state he will be in when he is finished with it this time