Scale tool not accurately keeping text proportions and line breaks

In Illustrator CC v22, I'm using the scale tool on a text box. While shift+dragging, the text looks correct (just scaled proportionally, without any reflow or stretching), but when releasing the mouse, there is suddenly some text reflow on some of the lines. This destroys some very carefully set line breaks. What I want to happen is to make the text column larger with the line breaks exactly the same.

This is not an issue of just scaling the box, the text itself is also changing size - but not accurately. What's going on?

I get the same behavior when using the transform function and manually setting a scale value. Checking/unchecking the "scale strokes and effects" in the transform dialog doesn't have any effect.

The most frustrating thing is that once I have scaled to a new size (with the broken flow), scaling seems to work just fine - I can use the scale tool to proportionally scale the text with the "wrong" line breaks. It doesn't come up with new text flow each time.

My only workaround at the moment is to convert to paths and then scale, but this is a pain and makes consistency a nightmare when trying to match path text to regular text. Any ideas?