Hi and welcome
First we are talking about an input device with an xy range guided by the screen resolution as the hw part. So all the kernel sees is a funky mouse. The software part that manipulates this input and configures its use is the secondary part. So it is not as complicated as it sounds initially.
The systemd only fluff is just propaganda, don't buy into it. You just have to spend a few minutes to write a service file for any other init for "that software" iptsd which is not even an official arch pkg but something someone has added to the community AUR repository. I am sure when it receives adequate amount of votes as popularity indicator it will move into community or extra.
You can just comment the line that adds the service file and the pkg will build fine, systemd is not a real dependency to it. But even if the service file is installed in your system it will not affect its use.
[Unit]
Description=Intel Precise Touch & Stylus Daemon
Documentation=https://github.com/linux-surface/iptsd
StopWhenUnneeded=yes
BindsTo=%I
[Service]
Type=simple
ExecStart=@ bindir@ /iptsd %I
The service file basically says you run as root iptsd interface name , which since I've never had a touch screen I don't what it would be like. I am sure Eric can take 2.4' to write a module type service file for it. The interface name you may get from lspci or lsusb depending how the chip for it is listed in the hw structure, but since I don't have one yet I can't help you. You may run lsusb and see it listed as something like ts0 or ts1 so the service command would be iptsd ts1, and if you have a service file written for it
# 66-enable -FS iptsd@ ts1
would get it enabled and running right away.
Now, I see 2-3 areas of issues with this, as touch screen in general is not a very common device around linux but with amd64 architecture based tablets growing and becoming cheaper I can see it catching on.
First, the kernel has to be built with that particular touch-screen hw device being enabled, or the specific module for it has to be added to the kernel's coverage. I'd give better than 50% chance that arch kernels have an MS touch screen device turned on.
2nd issue may relate to resolution, and many of those devices list an amazing resolution for something 11-13" big, when it is even hard to tell the difference with 1920x1080/1200 in a 24-30" screen. I think, not sure, but such resolution levels are fake yet, and the effective real resolution is still less than listed. On an "input device" that uses resolution as its input range that may be a can of worms.
3rd part is to get to this configuration and installation for that one time you'll set it up you might need a physical keyboard, which will have to connect through one of your usb ports, and I don't know whether you have one. Otherwise a system with an sshd service running that you can access from an other pc on your network may have to act as a terminal to the tablet.
Interesting platform, still pretty pricey, but if you need to have an i7 stored under the rear seat of your motorcycle running obarun it may be a good thing :) and when you leave the autobahn type of hwy to climb around a mountain you can alter the injection maps from economy to performance, or for having an emissions' test done.
For the rest of us a 2-4 core amd tower for 80$ will have to suffice.
Linux6.0 no longer supports AT input devices, a hook for an extra module will have to be added to use one of those pre-historic clunky indestructible keyboards, heavy enough so your fingers don't have to chase the keyboard around the table (if you have a table and don't do all your programming on your knees. :)