No one will ask OEM's opinions at that point(plus they're probably going to be somewhat compensated by mil orders).Relax people, Airbus and Boeing are not going to cut off supply of airplanes and parts to China unless they want to go into bankruptcy. What they want is dominance and money. They may want to block COMAC's progress but they won't want to destroy Chinese airlines market. Chinese airlines market is far far too large and important.
These companies have strong influences in their governments, they won't want their golden goose to be slaughtered.
Russian airlines bans (and many other sanctions) were quite clearly emotional, not calculated actions.
Never underestimate how govs can go over economic rationales for the sake of the perceived "greater good".