Bruce Clark asked, "Would the starting switches in piano motors
emit enough ozone to speed the deterioration of rubber pneumatics?"

I doubt that a starting switch would generate enough ozone to cause
a problem, but a constantly operating relay or other electrical
contactor to operate a magnetic coil during playing could be a problem.
Any "universal" type motor, which uses a commutator and brushes, will
generate ozone.

Ozone is a heavy molecule and will drop to the bottom of the instrument
case after it stops playing.  If your case is open on the bottom, it
should disburse into the room.  If your case is closed, it might
accumulate there over time and be worth looking into venting.  If your
instrument produces ozone, it probably needs to get out of the case.

Ozone is not good for people with breathing problems.  If you are
making a lot of it, you might want to consider making some changes.
I have never noticed any ozone around any pneumatic instrument myself.

There are ozone resistant rubber products.

Don Shenbarger