I'm right there with you on that...but I think
that, with Arduinos in
 particular, there is a net gain.  FAR FAR more people are into
 electronics and microcontrollers than would've been without that
 platform, and SOME of those people "take off the training wheels" and 
I wonder just how many extra people 'take off the training wheels' (that
is, take an Arduino and then go further) over and above those who would
get itno electronics/microcontrollers/whatever no matter what. My guess
is that it's small.
-tony