I'm not interested in starting endless debate about this here, but if you consider the success of Apple's products (among other examples), can you really draw the conclusion that the mass market doesn't want a one size fits all approach?... I doubt it.

I think we (geeks, open-source community,...) tend to forget that we are not representative of the market as a whole... And blame Nokia's management team as you want, but I don't think they are that naive as to not do any market studies before taking decisions.