The Pythons weren’t trying to lampoon advertising creative types, but they might as well have been.
More than once, I have locked horns with writers and designers who seem to think that a client’s budget exists to promote their art. That’s what grants are for, not ad budgets.
Successful advertising is advertising that meets its advertising objectives. Artistry matters only to the extent that it serves that end. I have seen woefully unartistic ads trounce consummately beautiful ads in head-to-head tests. And not always despite but, at least in part, due to their crudeness.
When you can pull off both — showcase your talent while nailing objectives — more power to you. But priority must go to the objective. That’s what the client is paying for.