Why Age of mythology not in Xbox Game pass?

I get that every one of the definitive editions are from the same developers but Microsoft own AOM so it wouldn’t be an issue to include it in the Xbox Game Pass, unless due to different developers they can’t include AOM Extended Edition.
I guess I will wait for AOMDE if Relic is working on it.

Because it’s not definitive, watch AOE2 HD. It’s Steam only. AOM DE will be a Forgatten Empires project.

Oh that makes sense.
Not sure if AOMDE will be a thing or AOM2, but what matters is that AOM need a revamp of some sort.