Direct Select Tool is causing shape to be transformed.

Suppose I have a Vertically-oriented hexagon such that there are three vertices are beneath the center of the shape, and three above (as opposed to a horizontally-oriented hexagon where two vertices are on the centerline).

If I select any individual vertex with the Direct-Select tool, I can move that vertex around without issue. If I select Two adjacent vertices, again: I can move those two vertices around without issue....

If I select *three* adjacent vertices, such as the bottom three, if I try to move the vertices around, the entire shape gets stretched, affecting the vertices that weren't selected.

I have no idea when this bug became a thing.
I am on 24.7.0 on Windows 10 right now.