"The real issue is that adding any kind of insert/insole into a shoe changes the insole shape; changes the relationship of the foot to the insole, and, as a result, changes the fit.
This is the same as buying a shoe that is a half size too big in the critical heel-to-ball measurement. It's what's known as the "orange peel effect."
Compounding all that, if the shoe was initially bought too large/long and the insert is being used to take up some surplus, you can end up with a shoe that is terrible for the long term health of the foot."
Are you suggesting hiking or work boots true to size with paper thin dress socks? Or we should be buying those shoes/boots with the thick socks we wear with them? For all due respect, those thick socks act as sole inserts especially with those extra cushion sole socks.
IMO different shoes should be fitted differently. For dress shoes I completely agree that insole inserts are unnecessary. But not everything is suitable to have that structured insoles.
Just my 0.02