psudo only allows one active mac address to be behind the client.
so if you have a CPE with a customers router or single PC behind it, it works great. If the customer plugs in a switch and tries to hook up two computers that try to get online, it won’t work as expected for them, and only one device at a time can receive packets.
Additionally it has less overhead than WDS, and reconnects to the AP faster in the event of a disconnect (WDS has to connect once regular, probe the AP to determine if WDS is supported, then reconnect as a WDS connection), Plus the option of turning off default forwarding on the AP works (To accomplish the same when using WDS you have to get creative and use a bunch of bridge rules).
For a backhaul, you should really avoid using WDS (or psudobridge), you should be using regular station and bridge mode, with no other devices connected, and then routing the data across a /30 subnet, preferably using OSPF (and a redundant path available), but static routing can be used if necessary.