Only men can shake hands
The handshake is an old custom that originated a long time ago. Back then, it indicated that your hands were empty and that you weren’t holding a weapon. Nowadays, we use it as a greeting and a way to seal deals.
Nothing indicates that the handshake is a masculine greeting. Rather than that, it’s a polite way of showing respect to someone. We don’t see why shaking hands with a woman is an empty gesture. Someone teach this person manners, please.