'APFSDS and heaviest armor' same as 'designed to engage another MBT [with their main armament]' I would say. If you count destroying MBTs with ATGW then you'll

'APFSDS and heaviest armor' same as 'designed to engage another MBT [with their main armament]' I would say. If you count destroying MBTs with ATGW then you'll start calling infanteers 'tanks'.