A lot of the competitive RTS crowd transitioned to MOBAs and it's hard to scratch that itch with an old-school RTS now. Having the full offline and online package was key of the time when those games were popular and you don't get that when the competitive space has moved on.

But you have a point. RTSs at their peak were super triple-A stuff, with mind blowing execution and production value for the time. Point and click adventures have a bit of the same problem, they used to be these massive technical showpieces and as a mid-size or indie thing they are a tougher sell when the modern equivalent of investment is going to absolutely insanely huge games in other genres. Even when a triple-A studio does one of those you tend to not get as much of a massive investment, and when you do (say, Total War: Warhammer, or even Manor Lords) they do see success. It's just never going to be the same because you're never going to call your friends over to show them Warcraft 2 running on your PC.