The problem with percents is they kinda hide information. Well not kinda, they do. Like I wonder what the numbers are because I REFUSE to believe that more games launched in 2020 and 2022, which felt particularly dead on Xbox both in terms of first party and third party games launching. The industry as well felt really dead between 2019 - 2022 due to COVID delaying development so much. 2023 and 2024 have also been when Xbox first party grew the most and we saw the most games launch from them with inherit Xbox Play Anywhere (including new first party Bethesda games). I know it's biased going off of how things "felt", but I'd also say there are a lot of real world events to back this up. And 7% of a 500 new game launches on Xbox is very different from 13% of 100 new game launches on Xbox. It's a tangent, but the same thing when we as consumers look at Microsoft's earnings call and judge Xbox based on year over year percentages. At this point Microsoft's gaming revenue is over 20 billion USD, what do any of us care if it sees a percent increase or decrease? Actually I swear once upon a time consumers didn't want corporations earning endless amounts of more from high values like that. Similarly when you look at hardware. Actual sales are mediocre for a console on the market for four years compared to the history of them. Year over year is different from actual hardware sales. Like the WiiU could've saw a stable or positive year over year, but it wouldn't change that in five years (its entire lifetime) it sold just 13 million.
It doesn't change the fact that regardless Microsoft knows they need to push Xbox play anywhere more and I think the big crux is the storefront on PC being so... unattractive. We can identify some basic patterns already. All Xbox first party is of course going to support and push it. Indie games seem to support it more than big publishers. Of the big publishers, Capcom, Sega, WB Games, and Bandai sometimes support it, but their support is wildly inconsistent. Also there's apparently been post launch Play Anywhere Support updates (like Dragon Ball Xenoverse 2 got it). For Sega, Atlus is a solid bet for supporting it. We'll see with Square Enix, so far they only support it when they port games during their "we want to support Xbox" campaigns. And that's about it. If a game is day one on game pass there's a good chance it'll be Xbox Play Anywhere but even that isn't guaranteed.
Microsoft does need to put in a lot of work marketing Xbox Play Anywhere as a benefit to both gamers and developers/publishers. I wouldn't be surprised if at the next GDC they release developer tools to make building Xbox Play Anywhere even easier or announce programs where they'll favor Xbox Play Anywhere on their platforms. Like with better tags. Oh, that's another potential issue with this analysis. If the people who did it went off of the Xbox store and searched for what tags the games that launched in these years had, they'd have been mislead. This is an issue with Xbox Play Anywhere, but a lot of games are in the program and lacking the tag or aren't discoverable on the Xbox app for PC (you have to use the Microsoft store). This especially seems the case when titles launch in the program. It's like Microsoft didn't have months to prepare their store pages. I've always remembered having to go through the MS store and download every other Xbox Play Anywhere game on launch day (Like a Dragon Infinite wealth, Metaphor, Soul Hackers 2, and maybe some non Atlus ones too... I have a type). Again this would still be a failing of Microsoft they would have to correct. I'm still not super into how we as consumers have come to blindly worship percentages as the success or failure of something. (though regardless of the actual numbers it's clear Microsoft has a mountain to climb with this pushing a decade old feature).