Acceleration for mob movement - does it exist?

If you look at the Abyssal rare mob with spears for example.
Their movement speed has no acceleration speed.
So they go from 0 to 100 in a flash.
There is almost no noticeable acceleration speed for mobs (bosses seem okay).
Visually it looks clunky.

I think it really lowers the quality and visual feedback of the gameplay if there is minimal or non existent acceleration speed.

In games like Starcraft 2, Acceleration speed alongside some movement animations (like the Oracle and Phoenix) greatly enhances feel and look of the gameplay. Its such an impactful stat that it can also be a grounds for balancing.

(Sorry GGG my feedback never ends, I'll put you to work)