Why would they not leave when they see a player injured right before a crucial game?
Why wouldn't they quit when there player will randomly decide to miss an important shot?
Why wouldn't they stay when a player they want and waited for couple of weeks to be seen at the TL had been bought by someone else?
More than that, due to the current auction system (non semi-auto system), they even may not be part of the real auction!!!
As you have written this is NOT a NBA2K, and it is a slow term game.
Whoever got into this game came to play it and not the NBA2K (or the eBay-game, as some gere do).
This kind of arguments remind me something that happens here in Israel.
There was a "Russian law" in the Israeli BB league, which mean that two Israeli players must be on court every time.
The coaches said that it is "not comfortable", although it was proven (at the three years assesed) that they can deal with it after getting used to the idea.
Any BB law that is introduced is changing the game a little bit and requires an adjustment.
The 3-Pt line, the traveling violation, Fouling out at 5 or 6 fouls, Having 2 half-games or 4 quarters, different league structure etc.
A BB-manager (and coach) needs to adjust to new laws introduced along the years.
Your argument could also be said about current Skills' drop.
A player (or players) who is the key player of your team is starting to lose skills.
Why this is OK?
Basicaly humans are more afraid of changes, but can adjust to most of them.