Open Source vs. Industry Standard?

So, I was looking for some various art programs for linux, and I came across this post. I must confess intrigue as I read through it. The open-mindedness of this particular professor surprised me somewhat, considering the more or less... "not-ness" of much of my particular school in general.

However, the comments on that post basically came down to one of these different boilerplate responses:

1) "OMG, ur liek so TOTALLY right! Macs suxxorrszzz!!1!!!" (When the author made no such mention, or even really any insinuation.

2) "D00d!11! Ur so ruining t3h studentz lives by teaching them OS inst3rd of teh industrie standards!!!"

3) "I admire your open-mindedness in trying to teach your students other options"

What was intriguing to me was that only ONE single person who offered negative feedback suggested they were actually working in "the industry", all other critics offered no such qualifications. The interesting thing to me is the fact that at least with Pixar they often write their OWN plugins/extensions/software. Many large studios use open source programs (I can't find a list, though there used to be some floating around on the 'net). I know a few people who work in "the industry", and I don't know that they're required to use any specific software. But just to make sure I'll ask on the art forum I'm a part of, though I'm pretty sure they use what they're most comfortable with, and it's their actual output that is of the most concern.

The moral of the story? Think critically before you post. Please please please!

Also, exposure to many different types of programs is NOT a hindrance! As a matter of fact, the more you know about various different skill sets, especially if you are proficient in them and skilled in at least one, the better off you will be.