I bet i'm not the only one to experience this! I don't mind constructive feedback on something that could be improved on but the guys I sometimes go flying with have just as many hours experience as myself. They are the same age as me! Especially when there is another non-flying passenger on board they just love to do a bit of showing off!.
Good thoughts precede this, however, the original description of the situation does not contain enough detail to form a good conclusion;
If the other pilot within reach of the controls was "showing off" to a back seat passenger, that's a problem, and you as PIC should not allow it. 50/50 that passenger is not interested in being shown off to at all, and even if they are,
your flight i not the occasion for the other pilot to be doing that.
You are responsible for the safety of the flight. If the other pilot buggers up the showing off, you might not be able to fix it, but you're still responsible for it.
If, on the other hand, your 130 skills are genuinely frightening a 70 pilot, one of you needs more instruction, and the other of you is not the person to do it - qualified training is in order.
bear in mind that the aircraft you are flying was provided to you, not the other pilot. Unless that other pilot is an instructor, and the purpose of the flight is instruction, that pilot is a passenger. Just because they are seated where they can reach the controls, does not confer upon them the right to fly, or you to let them.
The only exception to this would be that other pilot taking action to prevent an accident. You should not be allowing them to think that one might happen. If you are doing something unusual, you should tell them, so they remain confident in their safety. That said, few 70 hour pilots would have what it takes to correctly diagnose, then fix another pilot's mistake quickly enough to be effective. So if they succeeded, they probably did not need to in the first place.
When you and/or the other pilot have thousands of hours, the answers to this will be a little different. For now, for you, the pilot flies, and the passengers do as the pilot instructs them.