That's a really weak argument. A lot of technology we consider important now may well be obsolete in ten years. That doesn't mean we don't need it now.
Well, maybe not by Apple, but third party software plays windows media.
Most websites that stream audio (e.g., internet radio) or video (e.g., internet television) use flash players.
I use Pandora and Slacker Radio for the Internet radio. I go to nbc.com to watch TV on my iPhone.