Of course it should be done anyway as there will be a lot of used batteries in near future.
The necessity for recycling those batteries, without more, does not logically follow from their relative abundance in view of the purely economic perspective you posit. Why not just bury them?
It may be the scarcity of lithium that may drive us to take otherwise expensive steps to recycle such batteries.
The conclusory "of course" sets the argument up for a failure from the outset. Though it is not the only flaw.