Well if we believe his tweets all these years (lol) he would have set up a new studio or 2 three years ago when he took over and we might start to see those this year
Studios require people - you don't just build up a secret studio & not put out feelers to get people to work on these games. If there were new studios or teams, you'd have heard about them by now. Projects with established teams are a different story, though.
The reason Black Tusk was out there showing off Shangheist footage so early in 2013 was because they were getting their work out there to attract talent. They wouldn't have had a launchable game until last year even if they had stuck to that prototype & not become relegated to the Gears Studio.
I've said it before and i'll say it again - MS' problem isn't really 'games' necessarily. They've had healthy lineups, although they tend to be stacked in the back half of the year. They've been varied & diverse to a point, while lacking the robustness Sony can attract with indies/JP devs. What MS does lack is in software reception. The games review well, they're Xbox fans eat it up, but outside of that specific crowd no one seems to care about their output. Like, this year's lineup is fine really - State of Decay 2, Sea of Thieves, ReCore Definitive Edition, Forza 7, Ori 2, Cuphead, Crackdown 3. Sure, it lacks JRPGs, but this is the year that bucks the trend of 'Halo/Gears/Forza' for the Xbox platform. The problem is that, outside of Forza & Ori, the larger casual audience is just not engaging with their publishing efforts.
This E3, MS needs to break through their Xbox fanbase, who will be there anyway, and find a way to connect to the casual console gamer in a more significant way. They have a lineup that by all accounts those users should/may enjoy. Its just that audience just isn't looking for that from them.
There is an ongoing thread at the moment about Nintendo's lack of new game announcements but look at MS, since Gamescom 2015, we have had three major game announcements till now! In between it's updates, back compat games and controllers!
I understand the plight of Nintendo fans & Switch users, but at least Nintendo has the capacity to deliver quality software on regular timetable. Heck, the system is basically a month old and indie releases and upcoming titles for it look really healthy. It could be far worse considering it is a console whose hardware profile basically puts it out of consideration for the majority of 3rd party offerings.
However, for the first time ever in the history of the brand, Xbox fans will have gone a full year without any software announcements (E3 2016 was the last time). I'm not saying this to embolden the 'stockpile' narrative that some Xbox users seem to think MS is currently employing, cause everything i've heard about what they're working on mirrors the sentiment i've heard other people in the know claim as well, but MS is in an even more delicate position because they have this incredible piece of hardware that is going to hit the market, and really not a whole lot is going to be built to showcase it. If there is any purpose for a 1st-party stable of exclusives, its to showcase the speciality of the hardware you purchased.