"Actually", it doesn't make it really simple to do that at all. This is considerably more complex than copying a 'build all in directory' build file in and running msbuild on it. (Such a build file is the moral equivalent of the generic makefile that most C/C++ programmers have in their back pocket.)
And even tiny bits of code often need to be able to things that are rather basic within the framework. Importing System.* assemblies, for example.
Still smells like a solution looking for a problem.
I just tried it and it was simple enough to use. After using it though I agree -- I'd prefer my own rolled batch file as it has conventions built in that aren't to my taste.
By importing System.* assemblies do you mean automatically adding some boiler plate "using System.*"?
And even tiny bits of code often need to be able to things that are rather basic within the framework. Importing System.* assemblies, for example.
Still smells like a solution looking for a problem.