There is a formal extensional equivalence between Markov chains & LLMs but the only person who seems to be saying anything about this is Gary Marcus. He is constantly making the point that symbolic understanding can not be reduced to a probabilistic computation regardless of how large the graph gets it will still be missing basic stuff like backtracking (which is available in programming languages like Prolog).
I think that Gary is right on basically all counts. Probabilistic generative models are fun but no amount of probabilistic sequence generation can be a substitute for logical reasoning.
If you want to understand SOTA systems then I don't think you should study their formal properties in isolation, i.e. it's not useful to separate them from their environment. Every LLM-based tool has access to code interpreters these days which makes this kind of a moot point.
I prefer logic to hype. If you have a reason to think the hype nullifies basic logical analysis then you're welcome to your opinion but I'm going to stick w/ logic b/c so far no one has presented an actual counter-argument w/ enough rigor to justify their stance.
I think you are applying logic and demand for rigour selectively, to be honest. Not all arguments require formalisation. I have presented mine - your linked logical analyses just aren't relevant to modern systems. I said nothing about the logical steps being wrong, necessarily.