That's not exactly what they're saying. In the quote above, they are talking about framework independence, not platform independence. The wrapper executables are still platform specific, but framework independent. However the actual .NET modules in the package are platform independent, but framework specific. They can be executed without the wrapper executable by installing the correct framework yourself.
And as much as people complain about Microsoft's messaging with respect to .Net, there isn't really a simple way to explain any of this -- even to people who are deep into the .Net ecosystem. I feel their pain.'
