Reply To: Illustrator line weight in inDesign differs

Adobe says:

Scaling vs. resizing objects

Resizing and scaling are different actions in InDesign. Resizing is simply changing the Width and Height values of an object. Scaling involves using a percentage value related to the original scale (100%) of the frame.

The difference between resizing and scaling isn’t always apparent. A good way to see the difference is to resize and scale a text frame that has a stroke applied to it. When you double the size of the text frame, the text size and stroke weight remain the same. When you double the scale of the text frame, the text size and stroke weight also double.

(https://helpx.adobe.com/indesign/using/transforming-objects.html)