When I was a kid – cliché story coming up – we had trees, fields, meadows, ditches, whatever sort of terrain where to do all sorts of fun outside activities. Now there's here and there some artificial green between the concrete of tight urban housing. Also, my parents could still play outside safely without taking cars, immigrant gangs, drugs and other problems into consideration.
While I agree children these days seek too much comfort (probably following their parents' example: with adults becoming "fatsos" due to modern sedentary lifestyle, it's clear they're not going to (be able to) motivate children to be more active and outgoing), life just isn't the same as 50 years ago in lots of places in central Europe.
I assume the thought of becoming a local hero soccer/football player, athlete or rockstar might have motivated a lot of kids to take up sports and music years ago, but now all these disciplines are so global (on the scale of 7 billion people!) that these sort of dreams are so out of touch with modern life that they can't motive kids anymore and it really is easier to waste life in front of the television or computer.
It's too easy to point at one factor, such as TV or computer games, without taking the bigger picture into consideration.