[Goose]

So if the coaches are not the reason why players are leaving, what is?

I am sure that the coaches are a factor. In what way they are a factor is still under discussion. However, IMO this recent exodus is at least considerably influenced by the players looking at their future opportunities at Stanford. If even one very good player chooses to leave, the other players undoubtedly evaluate what that means for their own future. If the players as a group anticipate that Stanford will be significantly worse next year than they were this year, deserting the sinking ship makes lots of sense. This is especially true for players that are "good enough" to have other offers available (or think they do). This can easily lead to a cascade of departures, as we have seen at other schools.
 
Obviously, the widespread belief among players the program is going downhill would be a clear indication the coaches are unable to convince their team that the future will be better than the past. That is all by itself a leadership problem, "toxic environment" or not. This is an area where the unlimited transfers with no penalty applied really encourages players to leave. If you think you can go to a "better" team (and get playing time), why not? The fact others are jumping ship adds a powerful FOMO factor for those that have not yet done so. Thus the cascade.

[Goose]

So if the coaches are not the reason why players are leaving, what is?

I am sure that the coaches are a factor. In what way they are a factor is still under discussion. However, IMO this recent exodus is at least considerably influenced by the players looking at their future opportunities at Stanford. If even one very good player chooses to leave, the other players undoubtedly evaluate what that means for their own future. If the players as a group anticipate that Stanford will be significantly worse next year than they were this year, deserting the sinking ship makes lots of sense. This is especially true for players that are "good enough" to have other offers available (or think they do). This can easily lead to a cascade of departures, as we have seen at other schools.
 
Obviously, the widespread belief among players the program is going downhill would be a clear indication the coaches are unable to convince their team that the future will be better than the past. That is all by itself a leadership problem, "toxic environment" or not. This is an area where the unlimited transfers with no penalty applied really encourages players to leave. If you think you can go to a "better" team (and get playing time), why not? The fact others are jumping ship adds a powerful FOMO factor for those that have not yet done so. Thus the cascade.