This doesn't have anything to do with ham radio, except for the fact that some of the frequencies that the coalition is petitioning for are adjacent to ham radio frequencies, which introduce the potential for interference.

Hams tend to be very sensitive about interference, and rightly so. It's already pretty much impossible to do HF communications in urban areas due to the high noise floor caused by poorly designed switch mode power supplies, solar inverters, power over ethernet, etc.

No, it would only permit commercial non-voice, non-broadcast communications on frequencies not allocated to ham radio.

For a particular band, yes