It’s so bad that my fiancée has some bras that say she’s a B cup and others that says she’s a D cup. In order to go bra shopping, you have to actually try them on to find out if they fit.
If I had to try on underwear to see if they fit, I might not bother with underwear at all!
This is the case with all clothing.
All is a strecht… But yeah once marketing took over that function, it got turned into whatever the fuck we got now in the US🤡