Here's my data point, fwiw, for the khadas edge 2 and a Wacom One 13" Touch display tablet with touch screen capabilities.
With the rolling distro and the 6.1.75/vendor kernel, everything works (stylus, usb c one-cable connection to the monitor using USBDP Alt Mode, etc) EXCEPT the touchscreen does not function. Also, for whatever reason, in the Gnome Settings app under Wacom Tablet there are FIVE entries, not one. I attempted to compile a newer libinput, and this made no difference. I think, for whatever reason, the wacom driver in the kernel (which is compiled in, not modular) is too old to recognize my hardware correctly.
With the edge kernel image of the rolling distro (variously 6.10-rcX, 6.10.Y, and now 6.11-rcZ), absolutely everything, including the touch screen, works fine, but the USBDP Alt Mode does not work on the board (yet), so I have to use the Wacom 3-in-1 cable.
I have a non-wacom cheapo portable monitor with a multi-touch screen, and it works on either distro just fine (although it's not got a stylus, of course).
No idea if this is useful to you or not. Both monitors I'm using are 1080p, not 1440p.