It is intended to be used with AILerp, to tell your Seeker whether or not it "canMove", obviously. This has nothing to do with physics, and is simply a flag to tell AILerp whether or not to run the Pathfinding code in
That is true for some Unity projects, sure. The projects that use physics-based movement, and (though I'm not 100%, as I haven't used them) that is probably the case with other AI scripts in this asset. AILerp isn't one of those scripts, and doesn't interact with physics, instead using lerping to move along an exact path.