Proportional Scale with Selection Tool not working

Proportional scale doesn't seem to be working either with or without holding shift key. With the free transform tool, it is possible to select to constrain proportions, but when using the regular select tool there doesn't seem to be any constraining of proportions, whether holding the shift key or not holding it. I've hunted through settings for anything that could be affecting it, I've reset preferences and restarted, but nothing seems to work.