Another data point: My posts on using jQuery to replace the client-side ASP.NET AJAX stuff got hundreds of thousands of views before Microsoft officially endorsed jQuery and began supporting it. There are tons of .NET developers out there using the best tool for the job.
I think your criteria has to be who and what you're working on, not the platform. There are absolutely shops out there using Rails and Django with the same mentality that makes some Java/.NET shops miserable.
This is an over the top and even somewhat offending generalization. I don't know if all companies in Scottsdale are like this, but I can promise you that it's most definitely not the prevalent mentality in the .NET community nor in most .NET shops I know of.
"We were told we could not use 3rd party components, which sums up the prevalent mentality in the .NET community. So we did not use the popular 3rd party component CSLA, written Rocky Lhotka, a well respected member of the .NET community."
To make it clear... how can that mentality be THE prevalent mentality when there are these extremely popular third party components such as CSLA and Log4Net. They're popular because a LOT of .NET shops use them. They're extremely popular, because that mentality is not as common as you might think it is.