I have to say I'm deffo more attracted to FAT, yeti, mountain goat, that kinda bike. However! mass produced kona & stumpy steel frames still make respectable big Â£$, people lusted over them back in the day & as such people will deffo be bidding for them in future! ...so I see no reason why current day mass produced bikes wont be retro of the future. look at M900XTR, bolt on judy steerers etc, all easily bought items a few years back, now pulling decent Â£.
Elev12k, you're very right concerning jump bikes, IE spooky, BMW etc. look at what happened to the BMX market, really died off, then revival & mega Â£Â£ again