Games change. They have to change to stay competitive. I hate to tell the hardcore AoE fans but this game was made to compete with games like Dawn of War and the Battle for middle earth and so on. The face of RTS is changing greatly. Many games are forgoing any harvester units and going for all out massive amazingly dynamic, detailed, and fast battles.
For the AoE franchise to stay competitive in any monotary form it NEEDS to pull in these gamers. Giving them a little bit of what they want while trying to stay true to AoE (it has done a good job, regardless of what you belive). The developers work for a living. And that work requires them to try and get as many buyers as possible. Hardcore fans are nice, But never numerous enough to support an expensive project like this. They have to pick up the casual gamer who thought games like AoK were boring as watching hair turn grey. Either enjoy AoE3 or just go back to AoK. ITS ALREADY THERE. Why want another game just like it?