It's just the players today, the starters and superstars who set the tone for the game are very buddy-buddy and many have already played in enough games such that the competition of it doesn't matter. I feel like Lebron used to compete before he got into his 11th 12th 13th ASG... Kobe used to compete pretty much all the way til he retired... Curry and Harden are more the highlight type rather than the defense type even in their normal regular season style of ball...
If the 2019 ASG somehow featured starters (closers, really) of: Wall, Giannis, Butler, Paul George, and Ben Simmons against Westbrook, Wiggins, Kawhi, Durant, Ant Davis I think we would see a more competitive game. No chance that happens, but my example is more to speak to my feeling the lax style of the game is to blame more on who the ASG starters happen to be at this moment rather than an indictment on the game itself. You're going to see 3 quarters of pickup ball, but really we just want to see real basketball in the 4th quarter which I think those starters (closers) would provide. The closers now just follow the tone set by Lebron and Steph.