I don’t think Multics did hardware memory tagging.
Systems which do/did include Burroughs Large Systems (now Unisys ClearPath MCP), IBM System/38 and AS/400 and IBM i (the RISC versions of which used PowerPC AS Tagged Memory Extensions), ARM MTE, SPARC ADI, and CHERI/ARM Morello.
Systems which do/did include Burroughs Large Systems (now Unisys ClearPath MCP), IBM System/38 and AS/400 and IBM i (the RISC versions of which used PowerPC AS Tagged Memory Extensions), ARM MTE, SPARC ADI, and CHERI/ARM Morello.