The decline in football/sport being the number 1 street pastime has a lot to answer for as this is where so many technical marvels of the past honed their craft and became technical marvels who also had guile and resilience.
Even from when I was younger to now there is a massive difference in this area amongst kids - in the past, people travelled to neighbouring areas or well known melting pots for pick-up games against complete strangers, where pride was at stake but also a complete unknown element in what you were about to face and no real refereeing as the players self-marshelled.
Humiliating someone in games like those came with its own element of risk as you had no idea what kind of temperament the person had or whether he'd pay you back in kind or just try to take you out next time. That's obviously going to instill wit, improve reaction times and sharpen instincts - something you used to see in abundance with street footballers in professional games.
The additional aspects of any game played on surfaces far removed from pristine pitches come with interpretation of bounce and quickness of adjustment to predictably 'unpredictable' events - this helps defenders just as much as attackers.
I should imagine in countries with beaches, beach futsal (beasal), foot volleyball etc. Would be prevalent and its own place for convening for random games against a throng of unknown opponents. I've never played beach footy, but I have messed about with a ball on the beach, and it is so much more challenging than on grass. Your legs also feel lactic acid build up much sooner. Playing full games on such an exhausting surface against opposition you don't know comes with the additional element of commitment and sharpness. Countries like Brazil prided themselves on the malandro spirit - something assuredly being washed out as kids go into academies younger and play systems and structures rather than find their own way and perfect it. To put this into eurocentric terms, the stories of Best perfecting techniques by himself against walls and outside of United's tutelage are legion, same with Charlton.
This topic has many branches and reasons, but I think the decimation we've seen has obvious root causes, irrespective of nation.
Writing from a queue freezing outside a supermarket, so hope that this post is coherent.