During launch and landing, dust, dirt and debris may be stirred up. For non-gimbaling engines like the vac Raptors on Starship, can't the engine fairing/boattail be closed? I imagine titanium sheet for the purpose. Understandably, dissipation of heat from the engine is another important consideration but will the physical protection outweighs the thermal protection?
Raptors engine parts seemed pretty exposed from the bottom view.
So was S-IC.
But Saturn S-I wasn't.
Neither is the CBC.