So I would guess that the old SUSE Linux tagline "Have a lot of fun..." doesn't sit comfortably here?
Part of the proposition is the fun factor, not the hard-core educational outcome, and the multiple use aspect rather than the specific.
While the Pi may have some aspects that are a little distance from the ideal, such as the closed examples often given, there is no doubt that it has been successful in attracting all ages to the active side of technology, actually making something rather than merely consuming. It's done so in a wide way, having entry points for the purely educational, the fun and the project users. It seems to me to have done so in the spirit of open-ness too, even if the execution has had to be compromised from the ideal of full hardware open-ness in order to get produced. These things are to be celebrated far more than curmudgeonly elevating the compromises to the point that they detract from the good.