Calm down.
This game needs a lot of many more civs. This game, instead of representing entire cultural groups as it used to be, now begins to make new civilizations that are represented by kingdoms, e.g. the Burgundians. Several civilizations are badly named, e.g. Teutons should be Germans (unless there are new German civs) and Slavs (who are Ruthenians and represent only them).
As for the Name, these new civs are a matter of course, but there is now a fashion for non-Europeanness.
India is not a priority, we still have a small number of American civas (Mapuche, Iroquois, Mississippi, Hurons, Tupi / Amazons etc) and African (Songhai, Congolese, Mamulks etc.). Even Eastern Europe is under-represented. The best example of this is Dracula’s campaign in which we play three civs, and only a Romanian civ would suffice. Poles, Czechs, Serbs, Croats, Romanians and 1-2 German civs are missing (the Teutons are a Teutonic Order).
15 Indian Civs would be overkill - even in a game of Asia alone, it would be overkill.
2-4 new civs from the Indian subcontinent will suffice. Asia is also missing some Chinese civs (two civs only about specific groups - India and China?), Tibetans, Georgians and Armenians.
It would be nice to see Polynesians, Maourys and Eskimos too.
AoE 2 is such a famous and respected game that despite 20 years on the back of its neck, it is still developing. I think that it will also be an indicator of a good RTS for the next 20 years.
50 civs in AoE 2 it is obvious the question of what number will go up.
The devs won’t abandon their magnum opus - adding new DLCs with new civs will give them easy money, easier than creating a new game.
New Indian Civs will arrive sometime, but they are not of the utmost importance. But they will definitely come.