Crosmando: After all these years RTS games still create increased difficulty by giving the AI cheats; You can take out all their refineries/workers and somehow they still spit out hordes of units when they shouldn't have any money.
timppu: IIRC, that wasn't the case at least in KKND and KKND 2, and they aren't even new RTS games. In fact, one of the most important tactics was try to hit to the enemy refineries and tankers ASAP. The enemy would try its best to regain the supply chains but if you were able to prevent them from doing that, quite soon the enemy would run out of oil (money) and couldn't produce more units.
When I read the thread title, I was expecting a complaint more along the lines that the enemy units should be more clever, like sometimes fleeing and regrouping if they see that they can't break into your base in one stream, and maybe try some other route. That is harder to implement I guess, and it could be the game becomes too hard or laborious for most players.
I recall the complaints back in the late 90s why the enemy guards in Thief: The Dark Project don't act more like real guards, e.g. sounding an alarm
if they see someone keeps putting out torches, or locking down the whole castle if they ever saw an intruder, etc. I felt back then too they'd just make the game too hard, not fun. The Thief game could easily become impossible to play with too smart guards.
If I was one of the guards I would be far more concerned with the extremely rapid moss growth problem in certain parts of the castle.