The 2025-2027 time frame for dropping Intel support for macOS might be in the ballpark. By 2026 all Intel Macs but the Mac Pro will be classified as Vintage hardware. Apple doesn’t seem to want to support a new OS version on Vintage hardware.

The Mac Pro which still remains on Intel chips may skew that date out though. Apple did drop support for the 2014 Mac Mini in Ventura, and that hardware isn’t officially Vintage yet.