I get the impression from their wording that the licensed and unlicensed bands would have different thresholds and rules.
For unlicensed, it wouldn't be about registration, it would be about making effective use. It's hard to imagine a situation where nobody is making good use of 2.4GHz, so it should stay unlicensed, but the aspect of effectiveness is still there. Occasionally old tech that is acting like a noise blaster might need to be culled.
Licensed spectrum is nearly always used by subscription services - eg. your cell phone service.