It is well known that macroscopic objects do not have a quantum mechanical description based on wave function. They have to be described via the density matrices because of the enormous number (Avagado number) of particles involved, almost overlapping energy states, etc. Then, why apply superposition principle to Schrodinger's cat? Invoking linear superposition of dead and live cat and wondering how a cat can be dead as well as alive at the same time, certainly, lead to conceptual problems. Such problems come about whenever non-existent wave function description is invoked. It is important to remember that quantum wave function description is applicable only for microscopic entities in pure states. In that sense I wonder why so much talk about quantum teleportation, etc. A quantum state may be teleported, but not a cat!
I think you should check out Schrödinger's original writing with respect to that cat.
The whole thing was basically a joke about improper application of the formalism of quantum mechanics on systems for which it wasn't designed, so actually your criticism of the cat paradox is exactly the point that Schrödinger was trying to make.
This may have been obscured by "scientific pop culture", which is one out of several reasons why I am not a fan of that cat, either.
Macroscopic objects do have a quantum description in terms of wave functions; indeed the term ``macroscopic" doesn't mean anything sharp.
The reason the original cat problem is a paradox is because the distinction between ``alive" and ``dead" is, still, not well-defined. The corresponding study of other, better-defined, two-state systems is, since many years, standard practice.
Cf. for instance here: Preprint Creation and manipulation of Schr\"odinger cat states of a n...
and here: https://www.quantum-machines.co/blog/worlds-heaviest-schrodingers-cat-states-achieved-thanks-to-advanced-quantum-control/
They suggest the cat is in superposition because the decay product is in a quantum superposition. But I agree with your general intuition, there is a resolution to this that doesn't require invoking humans as privileged observers.
The key is that the cat itself is an observer. Its body contains trillions of atoms that are capable of becoming entangled and then spin-locked as part of resolving quantum states. Consider a simple entangled pair: once particle A is measured, particle B is no longer in a superposition, its spin state is locked to be the opposite of A. This means B can now act as a reference frame and resolve spin in future interactions.
Before A and B interact, B is in a superposition. But once A is measured, B becomes coherently locked, and measuring B will deterministically return the opposite of A. After B is measured and decoheres with the environment, it can eventually return to a superposed state, ready to entangle again.
This dynamic, entangle, measure, decohere, reset, happens all the time in nature. It doesn’t need human consciousness. The cat, with its many entangled systems and active neural networks, will be the first to know if the Geiger counter is triggered. From that moment, it's no longer a 50/50 superposition of dead or alive. The state decoheres before you open the box.
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