Biz seat I would say is the last generation of business class seats, similar to BA's very old CW product (remember the 2-3-2 configured recliners)? These recliners are now considered a PE product, although they're not as wide and recline less. There are several airlines that still have dated business class products similar to BA's hard product many years ago!

On the other hand, the Biz bed is the actual CW equivalent.