Microsoft is testing displaying a watermark on the desktop and in the Settings app if run on unsupported hardware. Microsoft is doing A/B testing of the watermark in Dev channel Build 22557. It remains to be seen whether such messaging will eventually start appearing in upcoming public builds as well.
https://www.notebookcheck.net/Microsoft-testing-desktop-watermark-for-Windows-11-builds-on-unsupported-hardware.601233.0.html