This is all valid points, except we can't predict how fast the number of qubits in a quantum computer will grow. Moore's law, even for classical computers, is just unscientific, in my opinion.

Also, quantum mechanics is not only about making computers faster, protocols safer, simulations and measurements more precise.

Quantum physics can shift how we view our reality. It can make possible what was unthinkable and unimaginable. Quantum teleportation, counterfactual computation and communication, quantum pseudo-telepathy and much more is just magic for a "classical" observer.