Possibly dumb question, but what do you actually run Q# code on?
Quantum computers can be simulated by classical computers up to a certain point. Like that article says, a 30 qubit quantum computer can be simulated on a laptop. Microsoft is simulating up to 40 qubits on Azure. Simulating around 50 qubits or so would need one of the world's most powerful supercomputer.
Note that the 'certain point' here is a practical limit of time/efficiency. In terms of computability, anything that can be computed on a quantum computer can be computed on a classical computer with exponential slowdown. It's the exponential slowdown that results in the practical limit.