Xcode 27 raises the bar for the deployment target to macOS 12, and my customers still request binaries for 10.9. 
What’s your strategy? Staying at Xcode 26 as long as possible (which at least supports 10.13), or just freeze the releases for people with <=12.? Does anybody have actual market share data?
BTW: XCode 26 isn’t compatible with macOS 27 (Golden Gate)
Here are my current usage stats:
1. macOS 26 (Tahoe) 45.12%
2. macOS 15 (Sequoia) 25.76%
3. macOS 27 (Golden Gate) 11.08%
4. macOS 14 (Sonoma) 8.84%
5. macOS 13 (Ventura) 4.46%
6. macOS 12 (Monterey) 2.39%
7. macOS 11 (Big Sur) 1.09%
8. macOS 10.15 (Catalina) 0.6%
9. macOS 10.14 (Mojave) 0.37%
10. macOS 10.13 (High Sierra) 0.26%
11. macOS 10.12 (Sierra) 0.02%
My current plan is my build machine keeps running Tahoe and Xcode 26, my dev machine runs the latest Xcode and my CMake file sets the deployment target based on the XCode version.
I think next major version of my product I drop Big Sur and earlier. People on old machines can download old versions if they need to install.
Food for thought on the development of these stats: do you see any major shift to newest MacOS versions in the last couple of months? Reason being: the collaboration for Pages & Numbers etc. got rail-roaded for older MacOS versions ever since the release of this creator studio suite. I always liked to stay a few versions behind, but this just got extremely enjoying on a production Mac.
I’m wondering if that makes people currently for example on Sequoia move to Golden Gate rather sooner than they would have.
When you say your customers still request binaries for 10.9, do they also expect those binaries to have all the latest updates? I’ve certainly worked at places where we would freeze the release for older systems so the binaries were still downloadable but no updates would be released for those systems. New products would also be limited to newer OS versions. My impression was that this worked well and was a reasonable compromise. I think generally speaking customers who wanted to run older systems weren’t interested in updates. They normally had a system that worked for them and they wanted to keep it that way, but that could still mean the occasional re-install.
Yes, and when they do, they’re usually satisfied with an older version; it’s mostly users with older versions of Pro Tools who request the older versions. My current products are compatible with 10.13. The jump to 12 affects nearly 2,5% of the market share (according to the numbers above)—that’s really a lot. I think I’ll keep my build system on Xcode 26 for a while longer.