No, they don't. Really, there are two Klondike Bluffs. South Klondike near the airport was pretty dusty when we were there. North Klondike looked nicer and the road was less rough.

This is BLM land, no reservations possible at this spot FCFS

No they are first come first served. At least last time I was there (10/2020).

No. First come first serve. They are all free. My go to spot in Moab, be prepared to drive far down that road to snag a site.

No they do not. Kind of by definition, dispersed camping is first come, first serve.