Played on last version but has been there allways.
I played 1 v 1 against outrageus AI on map Arabia.
The AI does normal stuff, goes with fast castle and starts attacking at around 8-9 minute. Then at around 15 min they stop attacking completely. They have full population at around 25 min and 2-3 k more score and better upgrades but they just sit near their main tc.
The only way to get them to attack again is to sacrifice my whole army by attacking them straight on and after that they seem to start attacking again.
Though this means they sit with full army under red keep and all get killed
The issue seems to be that after the AI builds first siege units they start doing very stupid things