This conveniently leaves out three key facts.
1) Breakthroughs in math are just as dangerous as breakthroughs in hardware. We don't know the algorithms we don't know. Shor's is a very new discovery in math, a baby. It was there all along, we had no idea. Can we optimize it, reducing the number of logical qubits needed by a large degree? Likely we can. We can also use AI to devise the classical algos to weed down the input to Short's without even needing to optimizing Shot's itself, for considerable gain. Likely we'll do both at once. We also don't know if there are other quantum algorithms out there that enable more efficient factoring methods, as the space of quantum algorithms is woefully unexplored, and it's entirely possible there could be a paper published tomorrow that changes everything. (We don't even know if qubits themselves are the way to go or if there is something exponentially better.) Basically there's a lot we just don't know in the math side here.
2) The majority of research on the hardware side is military/weapons research, advances in which we will not hear about. China in potentially investing 5 to 10 times as much in quantum research as all known US private-sector investment combined. But it's mostly all very quiet.
3) We have no idea the impact of upcoming AI discoveries on error correction using messy qubits. AI solved protein folding, and that was years ago. We can make messy qubits at scale with the current hardware, and if it turns out that AI-supercharged error correction enables a much greater degree of messiness then that changes everything.
Basically the threat is real, and there's no sense sticking our heads in the sand, despite that being a thematically appropriate approach for nostr.
I don't know where you're getting this, but thermodynamics and kitty-dynamics don't apply here. Schrödinger's cat is a thought experiment to illustrate the quantum/classic divide. His actual work is an equation that very accurately describes how the quantum state of a physical system changes over time, and that's what's really relevant here.
Quantum computers work, we know this. They work at the scale we have now (maybe 48 logical qubits, depending on who you trust), and they work just the same at the scale of 2,000 logical qubits, which is what's needed to crack Bitcoin private keys. (Unless we further optimize, in which case it'll be fewer.)
Scaling the sheer number of qubits does not imply "getting bigger" in the sense of lessening quantum effects. Basically increasing the complexity and number of these isolated quantum units is not allowing the system to become a large or "hot" classical object. The system remains fundamentally quantum.
