Hum.. I'am not so sure people did move on , you got plenty of isometric games being done and some with success like pathfinder, poe and wasteland.
I think it all boils down to me , what the lead developer of Disco Elysium said: "We made it with the express purpose of being failure proof in a way that, if it doesn't succeed, we still have not wasted five years of our lives, in that it's artistically solid, and we've said everything that we can say".
And if the devs from poe and poe2 said their piece and filled fulfilled I'am happy and proud to kickstarted them and helped them did their vision, not everything in life must be resumed to $ , they made enough to not die, and eventually be bougth by a Microsoft so..