PlaceComponent appears to be an exception. Strictly technically it is a tool (fires the tool observer, listens to input etc) but most users probably wouldn’t think of it as a tool as you can’t activate it from a tool icon button. It also lacks an instructor and shares cursor with Move.
I find it quite inconsistent though how it activates Select tool from Esc. Axes tool, which is another of those very rare tools that just carry out one single action, re-activates the previous tool.
I don’t think this one tool is enough to say Select has some sort of separate status, as Paint Bucket, Eraser, Line, Freehand, Rectangle, Rotated Rectangle, Circle, Polygon, Arc, 2 Point Arc, 3 Point Arc, Pie, Move, PushPull, Rotate, FollowMe, Scale, Offset, tape Measure, Dimension, Proitractor, 2D Text, Axes, Orbit, Hand, Zoom, Zoom Window, Position Camera, Look Around, Walk, and Section Plane all treats Select just as any other tool.
Under what circumstances do you want your tool to be deactivated?