If Gears 5 is any indication, the audience for Microsoft's first-party games on Steam may not be as big as we initially assumed. For the longest time, fans of Xbox franchises have been asking Microsoft to make its games available on PC.
Gears 5 is the first Xbox exclusive to be released after this major shift, but it's not looking great for its Steam debut. Despite landing on Steam's top-sellers list, Gears 5 only managed a concurrent player count of 10,196 since its release.
The numbers have declined since then, as is standard, but 10,000 remains a very small figure considering the size of the franchise, and the reach of Steam. Before Gears 5, the assumption was that the Steam audience is hungry for these big Xbox exclusives. For reference, 10,000 is not enough to land in Steam's top 25 most played games.
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While I have to admit that the Steam numbers for Gears 5 are low, I also do wonder how much of that is down to a) Gears not having that strong association with PC, unlike something like Halo, and b) Game Pass encroaching on those Steam numbers.
On the whole, however, I do think that the Gears audience is obviously largely in the Microsoft ecosystem, and feel that this stands as another reason as to why the arguments for any platform holder to go third party are bunk.