The risk of making an 8-inch cruiser do scouting work

Can a cruiser realistically operate a large number of catapult floatplanes?

It can, but only by treating many of the aircraft as expendable; that makes the role uncomfortable for a valuable 8-inch cruiser.

A cruiser can operate a large number of floatplanes only by accepting that many are expendable. That makes more sense for a lighter scouting ship than for a valuable heavy cruiser also needed in the line of battle. The Royal Navy could distinguish between scarce County-class heavy cruisers and more numerous light cruisers. It might reluctantly risk an older Arethusa before sacrificing one of its premier 8-inch ships. Aircraft losses, ship replacement, and morale all complicate the idea of a heavily armed reconnaissance cruiser.