Hey Keya, it’s just my humble opinion, but I feel that humidity is nowhere near as threatening to an instrument as dryness is. I have a decent fiddle in coastal Florida in a house with no air conditioning, windows open all the time. When I’m away, windows closed, still no air conditioning. I have experienced no problem with this. In fact, I think humidity improves the tone of the instrument.
I think air conditioning can be much harder on an instrument than humidity. I also worry about drying heat and dry cold weather patterns in northern winter climates. They can definitely cause splits in an instrument.
I do a bit of woodworking, and my personal theory is that an instrument, or many wooden items, become acclimated to a familiar range of humidity. Jolt the instrument out of its accustomed range of humidity and that’s when problems develop.