Things have changed though. It's not a free vs Free philosophical debate, it is about doing something illegal when you have a choice.
This is not just about teenagers. I can tell you that a legal copy of Microsoft Office for home use in Spain is really rare. Same for Photoshop, and other "essential" software that every home computer has installed, but nobody paid for it. It is, in practice, free.
I believe piracy is one of the reasons free software is not more popular, but well... I may be wrong.
This is the problem. Marketing is really effective to teenagers as they have not worked out the reality behind the branding yet. So free software gets less feedback and a smaller user base and so it goes...
"commercial software is the standard"
I'm just hoping that using 'the standard' gets a bit old and being different becomes a bit more popular.
Even today, GIMP is no Photoshop, Blender is no Maya, Openoffice is no Office, and the list goes on, and this has been after decades of trying to catch up. The truth is that for many domains, commercial software is the standard and has been shown to be adept at outpacing Free competitors. (This is not true in many domains as well.)
And besides this, a teenager who is a sponge for learning the coolest and most popular software could not care less about the tired philosophical debate about free vs Free, they just want to be able to play with Photoshop because that's The Thing.