TLDR: use the pen tool, switch to either the circle or rectangle shape, and hold shift while dragging the shape.
OK so the method/workaround/"fix" is to use the pen tool to create the shape, as opposed to creating an essential graphics clip (with the Text Tool) and creating an ellipse or rectangle layer in the EG panel. Go to the pen tool, click and hold, select either the circle or rectangle shape, and hold SHIFT while clicking and dragging the shape in the Program Monitor. Doing this will draw a shape as well as create an Essential Graphics clip in your sequence timeline. The shape you drew will appear as a Shape # layer in the EG panel. Oddly enough, from that same clip you can create a new EG layer (either ellipse or rectangle) and it will create the usual imperfect shapes (not uniformly sized) and with these shapes you are NOT able to hold shift to drag and resize the shape so that it maintains uniform Height and Width.
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