[BadInformatics]

The community staying very active has been the biggest factor here IMO. The predecessor to the current Definitive Edition, the rather disastrous (engine-wise, not content-wise) HD Edition, was created in part by co-opting community made mod content and hiring on some of the creators. This has continued for both the Definitive Edition and AOE 4.

Likewise, most of the biggest pros and casters started their careers 5-10+ years ago working on community tournaments and other grassroots events. Even though there's a lot more money now with investment from Microsoft, Red Bull and others, that grassroots core has stuck around and feels (at least to me) more fresh than the very corporate machinery around Blizzard RTSes. It's funny to think that the most anticipated LAN tournament is literally held in someone's apartment (https://www.ageofempires.com/news/nac3-tournament/)!