In contrast being shouted down at a meeting or losing your job is common and not protected. If your employer doesn't want to support your opinions, they are free to stop paying you. That is a freedom too.
I think it is very important that bosses embrace this view too, because otherwise you just get a lot of sycophantic yes-men, an echo chamber. The correct approach is to let everyone be free to voice their opinion before the decision is made: if you don't want their opinions, then what are you paying them for? Once a decision is made it is necessary for everybody to work towards that, but making a good decision requires lots of input, and those who disagreed with the final choice shouldn't be punished in any way, otherwise there quickly won't be any disagreement.