Haha, I completely agree with your point of view, but I think the game studio deliberately weakened the mortar, and I believe their goal has been achieved. The mortar is now a dispensable little toy.
For any FPS game, a weapon that can easily kill enemies outside the player's field of vision is devastating to the fairness of the game. In fact, this has already been confirmed in Rainbow Six and Battlefield 1.
Players will find the easiest way to play this game, such as the loiters in 2042, the drones and c4 in Battlefield 4, the mortars in Battlefield 1, and the sniper rifles that can one shot one kill. Then they will start to imitate each other. Eventually, you will find that almost everyone will play these things behind cover instead of taking points.
This is intolerable, but I still think that the current mortars should be better. The shells should be fired and land faster, and the shells should be changed to skill recovery, with a cd of one recovery in 15 seconds, allowing for the accumulation of three. This way, it should be balanced enough.