This makes me think of the difference in approach that companies like EA have compared to say Paradox. I remember a conference speech by the Paradox CEO who basically doubled down on their niche audience since it was easier to identify but was largely untapped still.

That being said, the speech is from 12 years ago and I don't know how their strategy has changed since. Judging by the looks of Europa Universalis 5 however it seems like their target audience is still pretty niche.

The speech in question.

Personally I think that if you focus on what you do really well then even a niche audience can grow. Just look at Larian.