I think the NBA should already be concerned. Miami is showing that a coaching advantage and 3 pt. shooting can make up for deficiencies in not just individual defense but overall athleticism and skill diversity. Now with the new CBA restricting budgets, player development and coaching is going to be critical. This game basically was like a lot of games for the Heat. Keep it close, hit 3s, don't turn it over/make dumb fouls, and give the ball to Jimmy in the 4th quarter the same way you bring in a closer in baseball. It's like the Patriots, basically. They don't make mistakes, make the game slower paced with their physical defense and Brady/run plays controlling the ball, and out-execute down the stretch. Denver's comeback would have worked if they didn't make crucial mental mistakes like fouling 3 pt. shooters, giving up and 1s, and turning it over.
The problem is, basketball is not football and it's always marketed itself as a sport where talent and greatness triumphs. Yes, you need a good coach, but it's much more important to have 1 or 2 of the absolute best players in the league. Also, you have to assume the 3 pointer is part of the reason that home court doesn't seem to mean as much anymore and this is a threat to the legitimacy of the regular season. You've already got too many games and load management making it seem pointless, now you have an 8th seeded team that didn't even win the first play-in game in the Finals.
The rule was always that if you can't play individual defense at a respectable level, you can't survive in a playoff rotation. However, the Heat are proving a good TEAM defense and having shooters is good enough when anchored by two all-defense guys like Butler and Adebayo. The sobering thing is, we thought we were a 3 pt. shooting team!