That sounds like an explicit confirmation that their intention is to keep ABK as an autonomous subsidiary in order not to run into regulatory issues.
And lets face it, if they stated up-front their intention was to make CoD exclusive, that would look explicitly anti-competitive to the extent that it'd definitely legitimize objections to the deal on those grounds.
Also. As I noted in another post the annual release + season pass strategy really does not work within Gamepass. Because it turns the offer into "buy a subscription and then buy another subscription!" Whilst severely distracting from all other similar product on the service for a month every year...
To be honest, the more I think about it, the worse a deal it looks for MS. The whole structure of Activision is so geared around this specific launch cadence I cannot imagine it not simply resulting in a severe loss of revenue for the unit as a whole. I really do not see a scenario where it makes CoD bigger and more profitable.