".NET makes it very easy for average developers to write GUI programs" - it makes it easy for any kind of developer, that's the defining characteristic of best frameworks.
I suspect that a lot of Director-level people in large companies don't see things this way. I don't have any direct evidence (i.e. PowerPoints), but all other evidence points toward someone sold Microsoft .NET as a "you can have cheap labor doing everything!" solution in the early 2000s. Folks who were middle managers back then have risen into Director and Executive Director roles, and since they're busy with office politics, haven't paid attention to anything else. They still think that a MS Studio installation can help a bad developer make a silk purse out of a sow's ear.
That's a feature; not a bug. The quality of these "enterprise applications" isn't as important as that: a) they came in under budget, b) (mostly) don't break, and c) when they do break they can be supported by existing support staff without investing anything more than what is effectively petty cash in training or additional resources.
For me the desired characteristics in a framework are the quality, stability and efficiency of the end product and then ease of use comes later. Its not that way for everyone, but I wouldn't simply say ease of use is the defining characteristic of the best tool sets.
