ALU has been struggling for ages between the group that has the bureaucratic power (the Chris Smalls fanclub) and everyone else. Individual warehouses are attempting to unionize themselves, usually without ALU help, and plan to decide on who to associate with later. There are various orgs taking their own approaches to unionizing Amazon, to varying success.
I'd say ALU itself continues to be in crisis but the project of organizing Amazon warehouses is very much alive.