post-quantum cryptography can be compared with a remedy against the illness that nobody has, without any guarantee that it will work. The closest analogy in the history of medicine is snake oil.

Good on them for saying that.

A "remedy against the illness that nobody has" is a good analogy, but it is important to note that it's an illness which there is a consensus we are likely to eventually have and a remedy that there is good reason to believe will be effective.

It isn't a certainty that there will ever be a cryptographically relevant post-quantum computer, and it also isn't a certainty that any of the post-quantum algorithms (as with most classical cryptography) which exist today won't turn out to be breakable even by yesterday's computers. The latter point is why it's best to deploy post-quantum cryptography in a hybrid construction such that the system remains secure even if one of the primitives turns out to be breakable.

That said, I think it is totally wrong to call PQC snake oil because that term in the context of cryptography specifically means that a system is making dishonest claims: https://en.wikipedia.org/wiki/Snake_oil_(cryptography)