The problem you are alluding to is there is no clear leadership of the team.
With the Sloan/Stockton/Malone teams, we had 3 leaders who did not hesitate to talk to the rest of the team, and yet the 2 stars still deferred to the coach as it was his team, he was the ultimate leader.
Look at all the great teams and they have players and/or coaches that step in and function as the leader the team needs.
Steph is widely credited with getting buy-in and stellar performances from perennial near-busts like Wiggins. Obviously LeBron is the de facto coach wherever he goes, and players listen. Popovich is a great example of a leader being able to get more than the sum of the parts out of a team. Jordan was the leader and the team followed.
The leader does more than just talk, he also shows and they follow his example. I remember reading something at the start of the season about Steph telling the team they needed to increase their defensive efforts this year, that this was their year to get back to prominence, and he backed it up with increasing his own focus on D and making it a focal point of what the team was doing. The leaders also hold the players accountable, but above all, they hold themselves accountable in a way that inspires great play.
We simply do not have a leader, not like that, not like what we need. Conley is too nice, Gobert is too intensely focused on his game and the refs, Mitchell is too self-absorbed, Quin is too rigid and soft. We do not have the guy that will step up and call people out in a productive way, or call themselves out, or meet them as they come back to the bench, or gather the team into an impromptu huddle on the floor and give direction. Our guys just high 5 each other, criticize publicly in passive-aggressive ways instead of discuss issues earnestly with each other, and rarely come together in the course of the game unless it is at the bench.
We need a leader, among many other things, but this is a big point we cannot ignore.