I don't think it has anything to do with laziness or open-mindedness, people today just tend to have a different perspective on ritual and symbolism than they did 30 years ago. It's not better or worse, it's just different.
50 years ago maybe people would have stopped and showed respect for the flag under any circumstances, but they were also terrible and nasty to kids returning home from Vietnam. Today people may care a bit less about the symbolism, but our soldiers are much better taken care of and respected (Westboro Baptist Church nonwithstanding), as far as my current perspective seems to suggest, in a very similar situation.
It's more about the material now than colored fabric.
People in the military or outside of it may not respect the flag as much, but no one is refusing veterans service at restaurants because they think they're babykillers, either, regardless of perspective on what's going on throughout the world. If the situations were reversed, I tend to think that you all would look just as bad (if not much, much worse) to the current generation as we do to you.
It's not necessarily better or worse (and saying this as someone who tends to put a little bit more in sentiment in ritual than much of the population), it's just a different perspective and outlook