stepping back from the performance comparison, one should just look at the current members in the e8X/f2X and m3/m4 forums. there are marked differences in the general age and $$ of forum members... there are of course exceptions
IMO even if M2 is as good as M3/M4, both cars would still appeal to the different members of the various forums and the public in general. No obsolescence but just great news for us BMW enthusiasts