Wearing a shirt doesn't mean they're openly advocating for it within Microsoft's studios. If they already feel like they're treated well, they may not see the point for them...doesn't mean they don't see the point for other developers at other publishers.
When you're talking about unions, it really is 'not my studios, not my concern' - mostly because of the business implications. If he says 'Yeah, that shit at Rockstar is BAD...No idea what needs to happen, but they need to get that under control' you don't think there'll be blowback from Take-Two about it?
Plus the question was NOT about the industry - it was directly about conditions at Microsoft. "What are your expectations of the people that work under you and are making games in terms of the extent to which they should or shouldn't crunch, what is a fair thing to ask of your employees… do you have guidelines?"
That, and the entire response about their work making development sustainable without crunch, was something that didn't make the quote cut.