Exactly.
For me it's like a multiplier. I have a base level of interest in some game, and then that is affected by external aspects. If it's on Steam or GoG, which are feature-rich, easily accessible, and where I have a reasonable level of trust in the longevity of my purchses, the multiplier is 1. If it's exclusive to something like Origin or the Epic store the multiplier is e.g. 0.6, and the game will have a harder time competing for my attention and money. (And if it's UWP or console exclusive, which harshly reduces the utility of my purchase, it's lower still)
That's perfectly reasonable, but again I am not the least bit surprised other storefronts think they have to do aggressive maneuvers to gain more attention to the behemoth that is Steam. Hopefully this is just a timed period. It is also a great way for a game developer like the one making Ashen to gain some attention with the launch of a new store compared to Steam that has literally thousands of titles which can easily be overlooked.