You’re disregarding the psychological damage of being in a steampunk hospital
Me, in a neck brace because even slight movement may snap my neck
“Oh no, that looks like one of them new steampu-”
Cringe
Snap.
I wake up, the nurses and doctors are there to greet me and they get to about “G’day most distinguished gentlem-” before I turn off my own life support
The tarnish is often seen as unsanitary, though it’s not, and unsightly, so the upkeep can be a lot.
In fact a lot of brass and copper decorative fixtures are clear coated to prevent oxidation, but then they also prevent the antiseptic properties of the metal as well.
Nosocomial infections are a really big deal in hospitals too. I wouldn’t depend on copper alone to kill bacteria; how well does it deal with getting bleached down?
For the OP, if some snot-nosed child wiped his hand on the giant greenery wall, the bacteria flourished on the wall, then the AC brought a bunch of germs into an area for the immunocompromised then you’re not gonna have a good time