Just my opinion and sort of on/off topic regarding Xbox player base. Yes, it would drop off due to the PS timed exclusive content, etc.
On the flip-side I believe however, once the exclusivity ends Xbox players will return to experience those strikes they weren't able to fully experience from the get-go. As an owner of both brands I do agree it should have been a fair contents release.
Now... IF I were the marketing/finance officer for Bungie/Activision I would have contracted with both Microsoft AND Sony.
Give each their own sets of exclusive content, then release DLC's of that content, and repeat the cycle.
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