The whole concept of transmog is poor especially in the context of bg3.

Let me expand.
A. it is always an inferior solution to modding. Permutation of in game items will always be lower than permutation of in game assets and creator contents.

B. It removes the uniqueness of items. Even if you don't use the system it lower the appeal of finding an awesome item. Since your random base item can now be changed to that same item that item appearance is de facto no longer unique

C. It disturb the graphic balance the game maker intended and carefully and painfully constructed. A game is an art form, and why not respecting the artists? If you listen a song you wouldn't think of asking an artist to change a specific line would you?

D. We have dyes and clothes to buy for the ones caring deeply on how they look

E. It damages character progression having your paladin look identical in full licorn coloured plates from level 1 to 12 doesn't really translate the journey of an adventurer, does it.