Soviet era tanks were designed to be use in Blitzkrieg strategy, as they saw its success in European battlefields during WW2. That is the reason why these tanks were made with basic armoury and less protection to lower cost. Little to no night fighting capability. The emphasis is on quantity rather than quality. Crew survivability in these tanks were not the priority as the soviets knew they can replace these dead crews and tanks easily if they are destroyed in battle. For NATO, the strategy is opposite. Quality over quantity, protection of crew is priority, combined arms strategy. In modern battlefield, tanks need to operate with infantry, air cover and artillery (at minimal) in order to be successful. Tanks must never operate alone, otherwise, it becomes sitting duck for anti armour weapons. With the advancement of weaponised drones, it is even more important for armour tactics to change according to times. Whether or not these Soviet/Warsaw tanks can transit to the modern warfare is debatable.