An early small ball 5 maybe, but traditionally more of a small 4 (smith). Same with Millsap really. No arguing both are better defenders than Morris and gimpy Hayward, so it’s no wonder Al’s d looks better with them. He was the one playing the 5 though.In ATL he was paired with Josh Smith who was also a defensive minded 4/5.
Pairing Al with MaMo or a gimpy Hayward at the 4/5 put 100% of rim/lane protection on Al's shoulders.
Go look at Al's efficiency numbers when he played the 4 vs the 5 as a Celtic.