Kant's 20 thalers objection to the Ontological Argument

I’ve been thinking of this way of putting one of Kant’s “20 thalers” objection to Anselm’s ontological argument:

1, When we say “x is greater than y”, what we mean is that what x would be like if it existed is greater than what y would be like if it existed.

Now, Anselm claims that a perfect being that exists in thought and reality is greater than a perfect being that exists only in thought. But this does not seem true. For what we need to compare is what (a) the perfect being that exists in thought and reality would be like if it existed to what (b) the perfect being that exists only in thought would be like if it existed. But the answer here is that the two perfect beings would be exactly the same under the hypothetical condition that they both existed in reality.

(A query: Wouldn’t the being in (b) be a self-contradictory being if it existed in reality, since it would be a being that exists only in thought and yet that exists in reality? This depends on how the counterfactual is resolved.)

Note that this objection does not apply to the necessary being versions of the argument (like, perhaps, Anselm’s “cannot be conceived not to exist” version). For a perfect being who is a necessary being would be greater, if it existed, than a perfect being who isn’t a necessary being, if that one existed.