Well stated Keith.
I’d also like to add to my previous set of situations wherein an oil leak DOES require attention one more: the main seal. If oil is leaking out the front on an engine with a timing belt, it needs to be addressed. Oil seeping past the front main seal can and will damage a timing belt.
Anyway, I didn’t see that in the OP’s post. My tsrong impression is that the shop recommended unnecessary expensive gasket replacement with no real purpose other than revenue generation.