Beautiful = full of beauty
If you’re only “beautiful” on the outside, then you’re technically not beautiful. Because you’re hollow on the inside.
To call someone beautiful, as he or she looks stunning or radiant by looks, is like polishing their outer coating to make it lustrous and shiny- even that fades away soon
As it fades away, their insides start to show, whether it’s golden or rusty.
Which means a huge percentage of their beauty is mostly on the inside with only a coat/mask to show on the outside.
If you would like to comment on how appealing and attractive their outer coating looks like, just say he or she looks visually stunning, or some other synonym phrase for it- pretty could also work.
Call someone beautiful once you fully know the person, in which any outer coating they put on to polish themselves just adds a little sparkle to a person who is wonderful, amazing, and admirable as a whole.
To sum it up it’s pretty much a huge contrast between
You look beautiful
You are beautiful
It’s all about perception.
Seems stupid to give a random definition to a common used English word, but in a way some people forget the true meaning of a word and start using it as a filler word.