If your employer’s “shop,” or just the part of it which concerns you, is Microsoft-based, then it only makes sense that they would be using .NET, and it is a very nice benefit that they are offering you training on it.

There is nothing like .NET to give you a fresh, new appreciation of Perl.   ;-)

You have surely heard of TMTOWTDI.   Yes, indeed:   “there is more than one way to do it.”   Specifically, there’s the right way (Perl...), and the wrong way (.NET).   ;-)

In all seriousness ... learn about both of them.   Computer programming systems are just tools, and the more tools you are more-than cursorily familiar with, the better off you’ll always be.   Every “shop” is going to select its own personal modus operandi and they almost never change it; nor (usually...) should they.   But you are always going to be bouncing from one company to the next ...

Don’t invest your time trying to get them to “switch to Perl.”   For them, it probably is not a defensible business decision, nor is it technically mandated.