Microsoft has fought their asses off all generation, unbundled Kinect, multiple price reductions, 2 revisions, released their biggest IP (Halo, Gears, Forza), has full AAA support, paid for exclusives/timed exclusives (Titanfall, Tomb Raider, PUBG), released a handful of new IP (Sunset Overdrive, Quantum Break, ReCore, Sea of Thieves). They just cant seem to get out of that ~8 million/year baseline.
It may not be a bad thing for XB actually. As long as the 'XB2' launch goes much smoother. While the 360 was a strong launch and a massive improvement in many ways, just focus on the fact that the 360 was unexpected and a true underdog. People love when an underdog rises up and goes above and beyond. If 'XB2' has next gen level hardware that matches the price, and that price is reasonable, then a worthy and more lengthy list of exclusives to go with that launch and the following years, could very well give 'XB2' the same boost that 360 had. Right now, while there is still room to go down since they aren't hurting that bad overall at this point, especially in comparison to the 360 sales, XB has plenty of room to move up and improve, which makes them potentially dangerous.
I see XB1 coasting for the rest of this gen for the most part, so it leads me to believe that we will see Switch surpassing it by the end of 2019, which may be short lived if we see a 2020 'XB2'.
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