One thing I've seen in general is that even at high levels, dumb melee brutes have their uses if properly supported. Not to say that those poor excuses for giants are any good, but in general big melee beasts can do well if buffed and geared up and supported in combat by casters. Due to all the anti-casting investment that gets more and more intense at higher levels, simple melee monsters often benefit from having less build resources dedicated to dealing with them.