In the end it is a question of taste: there is good taste and bad taste
I mean, I think at pinball as an overall multi-sensorial experience, similar in a way to cinema. Enjoying a movie is very much linked to the cultural level of a person. People with lower education enjoy simple, sfx rich, Hollywood movies. Educated people prefer independent movies, without many sfx but with a spirit, a soul. Of course the first group of people perceive the Hollywood movies as full of soul too (sometimes actually also the second group can appreciate those same movies - even with sfx and big budgets it can happen). But I think it's impossible to explain to a person of the first group why a movie from the second group can be so amazing, without bells and whistles, amazing sfx, and so on.. It's a cultural process of development.
I think that this discussion about the B/W vs. Stern "touch" is not only related to gameplay, but about the overall multisensorial package. A cultured person can understand why a movie with low budget can be much more visually and mentally amusing than a mega budget new Hollywood commercial movie. It's about taste, small subtle elements that bring joy and surprise, etc...
A pattern looks to me happened in many different fields over the last decades: the artistic quality and "soul" dropped and has been replaced with an ultra technical, cold approach. Lots of quantity produced with the help of software/code, but less space left for the human side of the art.
Now, I am not saying that the Stern lovers are only people with a lower level of culture: probably its just a group of people that focus mainly on the rules of the game, on scores, on number of features, perfection of the code, complexity of the game.
B/W lovers tend to focus also on the historical meaning of a machine, on some elements of the art (for older machines), on simplicity (less is more) as a link to a time when the world was simpler and better and more joyful... and many other similar elements. For me it's like that. It's similar to play vinyl/cd vs. mp3. I love holding a vinyl, letting it go all the way without skipping, smelling it, etc.. as opposite as bulimically skip trough thousands of mp3 without really LISTEN to them with the heart.
Early SS: vinyl '90 B/W: cd
Stern: mp3 (in the best lossless format )
Note: what written above does not apply to WPC95 machines! (I see them as in between the two groups)
Note2: sorry for my english, I am from Italy!