You're not allowed to say that it's not reasoning without distinguishing what is reasoning. Absent a strict definition that the models fail and that some other reasoner passes, it is entirely philosophical.

I think it’s perfectly fine to discuss whether it’s reasoning without fully committing to any foundational theory of reasoning. There are practical things we expect from reasoning that we can operationalise.

If it’s truly reasoning, then it wouldn’t be able to deceive or to rationalize a leaked answer in a backwards fashion. Asking and answering those questions can help us understand how the research agendas for improving reasoning and improving alignment should be modified.

"entirely philosophical"

I don't think this means what you think it means... Philosophers (at least up to Wittgenstein) love constructing and arguing about definitions.