If all workers are just salaried, then no work place that requires 24/7 staffing would function correctly.

Absolutely no reason they couldn't considering fixed shift time schedules are a thing too.

No one will be willing to work rotating shifts without hourly/shift bonuses.

Little to no reason to have rotating schedules... and the incentivization of bonus pay for abusive scheduling practices is just unnecessary. Hell you can do that even with fixed salaries in play where bonus pay is given to those who cover down undesirable shifts. Or periodic performance bonuses are based on hours therein. None of that is solely in the domain of hourly worker compensation.

Months have different numbers of days there will be no way to divide out shifts evenly. Then every worker would just try to get on the crew least amount of shift scheduled or the schedule not interfere with holidays.

And? that's life and no one is going to give a fuck about an extra day here, or one less day there as long as things run smoothly and needs are being met.

Also none of the above has anything to do with salaried vs hourly.. or anything that does not already happen anyways.

Really none of the claims and arguments in this post make any sense. Really just sounds like wanton speculation based on fear of change.