From testing in Conn, Mortars only appear to reliably hit within the range that one would use a Razor, which undermines their intended use case, since Razors are better in almost every way at that range.
Long range weapons need to have more projectile speed to be useful, not less. A better limiting factor for long-range weapons is turret traverse speed and/or energy efficiency, which prevents long-range weapons from being used effectively in close quarters, while still allowing them to perform well at their intended range. At the moment, mortars are now useless.