Again, I'm 100% with you. But making certain features worthwhile is also somewhat subjective to the player.
Player A: When it comes to signing a practice squad, player A looks at those 8 players and realizes they have chosen those 8 prospects out of those 37 cut (90 to 53) that played well enough to stay a part of the team. Player A well knows that any of those 8 can eventually be starters and a keen evaluation is absolutely necessary for the benefit of the team.
That same player comes to the offseason. Their head coach led their team to a 5-11 year, and they has parted ways with said coach. An offensive coordinator that was with a team that passed for over 4000 yards and was in the top 10 for rushing is available. Knowing well enough that the player's team struggled immensely on offense, Player A chooses this coordinator to be the new Head Coach.
Player B: Sign 8 random guys they want to fill the practice squad, only thinking of them as immediate band-aids for an injured player and any other use is nothing more than satire.
Offseason roles around, and this one coach has a cool name and went 10-6. Screw stats, sign him up.
To me, the player can bring the game farther. But to your point, a coach should have a large impact on players (progression, regression, on the field play). You should never have to ask those questions in a good franchise mode.