just had this issue pop-up for me suddenly 24 hours after installing Windows 11 22H2 update. This is a non-touchscreen laptop, with no detachable keyboard. At the beginning of today's session windows suddenly informed me that it was running in tablet mode, but the only evidence of this is the tablet pc controls in control panel, and the checkboxes in explorer. Obviously 22H2 is not quite ready for release. I hope that before they do release the build, they give us back a way to change tablet mode on/off at the users' preference, not according to to how windows wants to.
There might be an explanation as to why the tablet PC components are even available for me in the first place. I installed 'Super Display" on my new Lenovo Yoga 13 android tablet. and the PC part of the software installed a virtual display device that allows me to use the tablet as a touch screen monitor for windows. The monitor also has native built-in support to act as a secondary monitor for a PC via HDMI, but its touchscreen capabilities do not work with that. for now, I will uninstall the PC side of Super Display and see if that fixes things.