is youth losing its roots?

Listening to prog is like reading classical authors: it is not obvious and demands some time and concentration. I would suggest all the young prog lovers to teach their friends.

And teaching is not something easy: you will have to build a teaching program. For example, do not introduce prog with "A Plague of Lighthouse Keepers" or the most strange Gentle Giant or Soft Machine songs. Select a choice of midsize (5 to 10 minutes), not too complex songs from the masters of the genre (from symphonic, art rock, psyche, prog metal...), make one or two CDs with them and convince your friends to listen to them more than once. Then ask them what they liked and what they didn't and why. From there, enrich your selection.

I cannot guarantee that you'll get all of your friends addicted to prog but you'll surely gain some.

I guess teenagers won't know anything that isn't played on Radio 1.

i know what you mean.
i'm 18 and i was 17 when i got into prog, but i still haven't met anyone of my age who likes prog. well, there are a lot of guys liking dream theater and pink floyd, but they don't know any other prog bands.
it has become my life goal to find someone of my age who likes prog, but the youngest prog lover i've found was 38...

how frustrating

Well...unless you have parents (like my children do - I'm 52) who were deeply into prog at the time it was THE music of its time, it is understandable that teens are no longer even aware of the existence of progressive music.

What do you hear on the radio? what do you see on music TV channels? What CD's are on display in record shops? prog?

If you are a prog fan and in your teens, you'll have to do the job: teaching your generation that there is something different to listen to than RnB, rap, techno, house or alternative rock. (Though alternative rock is far to be the worst place to start to explore more complex things).