The comparison comes up constantly in meetings: “for that price we could buy this much outdoor.” It is misleading, because it compares a surface to a relationship.
A billboard does not answer comments, does not defend the product three weeks later, and loses nothing by announcing anything at all. A creator puts their name on every post, and their audience reminds them of it immediately.
That is what makes influence effective, and also what makes it fragile. A brand that forgets it gets respectable reach figures and no real effect.