You are right for Starcraft, as it is early game focused. But Developers do extremely fail to design Starcraft clone. You should not loose in because you did run out of resources or enemy did make cheap rush move, but because your enemy has the better strategy.
Starcraft is designed like a boxer to knock out opponent in first round, if it does not work he is out of stamina. AoE is rather a technical boxer and that can go for lot rounds.
Issue is you can’t put AoE units and buildings into Starcraft gameplay, it won’t work. Because, developers don’t understand what they have to adjust. Starcraft units are designed as units that do damage every single target fast. AoE units do damage only one thing fast. So while even weakest unit like Zergling will eat Fortress in secs fast for breakfast. Majority of AoE units won’t even scratch a house.
AoE is mid and endgame focused. That’s what AoE units are designed for.
By the way in AoE you can make more decisions in mid and end game, as you have greater economy to back up your plans. And that’s why you can play AoE for hours, as it is still fun to do so.
1 game being 4 hours long can be very fun, if done right I would compare it to a dark souls boss fight, it feels very rewarding to finally win and not regretful to lose as it was a decent fight.
You are right, that’s accusation to be fun can be rare. That’s why I do think AoE requires more meaningful tools for the mid and end game.
-first of all better mid and endgame resource production, to produce actually tools to win.
-more room on the maps, to actually build infrastructure you need.
this alone will have great impact on that issue.