

I thought so too, but I think the acceleration is an optical illusion due to the warhead coming in slightly towards the camera. I also don’t recall any ballistic missiles carrying a terminal motor that kicks in that late.
That’s usually only for cruise missiles. Gravity does a good enough job of giving the warhead speed.
Not sure Iranian missiles are that advanced. Even the Soviet missiles designed to take out supercarriers only had the most basic terminal maneuverability. And those were done by fins. Even the US has only recently caught up with that level of ballistic missile tech by the mid 2000s