How is improved unit responsiveness from the last patch favoring rifle grenades? It means you have now more reaction time to escape. Units clumping up more affects all AoE weapons, why do Rifle grenades get singled out of this? It is those weapons that you cannot dodge at all that profit most from the last patch, namely stuff like tank shells.
Rifle grenades are telegraphed really poorly compared to other grenades thanks to their huge range.
If a volksgrenadier squad wants to throw a grenade, they have to close in to throw it with an obvious animation, and after it lands there is a time. The enemy can suspect one is going to get thrown from the moment the volksgrenadiers break cover to close in for the throw.
Now grenadiers on the other hand give the enemy little time to react. Grenadiers don't have to break cover to launch a rifle nade, the animation isn't that obvious as stationary troops kneel and go to prone from time to time by themselves, and the grenade explodes on impact. The enemy has to suspect a rifle grenade all the time and can't look away because the entire cycle of 'break cover > close in > animtion > fuse' does not apply to rifle nades.