I'm not comparing Xbox to PS4. So I don't see why you continue to.
I'm looking at Xbox, on its own, and comparing it to itself (2018 vs 2017). I don't see a way that it'll be up YoY. And the numbers could be down for several good reasons. No X launch this year, for starters.
First PUBG & Sea of Thieves is going to boost sales in Q1, Last year the only major release was Halo Wars 2.
4k gaming on Xbox one X
Exclusives 2017 vs 2018
Game pass announcement
Holiday 2018 vs 2017 (expect price drop & bundle on Xbox one X and Xbox one S for <$199.99)
|XB1 2017 release||XB1 2018 Release|
|Halo Wars 2||Sea of Thieves|
|Cup head||Crack down 3|
|Tacoma||State of Decay 2|
|Forza 7||Forza Horizon 3|
|Super Lucky Tails||Ori & The will of the Wisps|
|Deep Rock Galatic|
That's only what we know about, Microsoft could have further surprise for 2018 at E3.
Tommy Jean, CPA, CGA