What is the term used to describe substituting a person for something they did or created?

It appears the closest term with the meaning you desire is deferred reference. To quote from Wikipedia:

In natural language, a deferred reference is the metonymic use of an expression to refer to an entity related to the conventional meaning of that expression, but not denoted by it.

As you noted, the "Yeats is still widely read" example is very similar to what you are asking for (as the referent is the poems written by W. B. Yeats but Yeats himself is the direct reference).

They are called Placeholder Names

Placeholder names are words that can refer to objects or people whose names are temporarily forgotten, irrelevant, or unknown in the context in which they are being discussed.

Consider Alice and Bob

Alice and Bob are two commonly used placeholder names. They are used for archetypal characters in fields such as cryptography, game theory and physics.1 The names are used for convenience; for example, "Alice sends a message to Bob encrypted with his public key" is easier to follow than "Party A sends a message to Party B encrypted by Party B's public key." Following the alphabet, the specific names have evolved into common parlance within these fields—helping technical topics to be explained in a more understandable fashion.

[Wikipedia]

Eponymy

When a thing is named for its creator/discoverer (or anyone else with which it's associated) it's known as eponymy. This is often done via explicit branding, such as Ford automobiles or McDonald's hamburgers. Over time, a brand name becomes so well established that "automobile" or "hamburger" becomes assumed, and "drive a Ford" is sufficient to convey the meaning.

In this case, it's not a conscious branding exercise, so we might need to qualify it as a particular type of eponymy. For that, however, I can't really come up with anything solid, so if anyone else has ideas, please edit this paragraph to specify that it's "_____ eponymy".

Eponymous was the first word that came to my mind as well, but I don't think any of the answers so far hit the spot. The question isn't about a machine or task named for its creator (eponymy: example = the Dyson vacuum cleaner), or about a name used as a generic placeholder (placeholder names: example Alice and Bob.).

Its about using the name of the person with agency as the "doer", and treating them as the doer, even though the actual doer is in reality a machine or other entity they have directed to do the action.

Agency, principal, or locus of control come closer to the concept but I can't think of a specific word. Hope this helps though.