Using location and/or background audio are ways of keeping an app running in the background and not being killed by iOS.
Obviously this is a bad thing for any app to abuse but in this context it’s up the user to write in ‘cat /dev/location > /dev/null &’ into the shell or a shell script.
why do you think that it would be lightweight compared to (co)Lima? it's only being done on iOS because Apple won't let anybody do any better. Apple Silicon mac's have far better options available
I wonder what kind of expertise and specialized equipment is needed to liberate, as in get Linux as the first thing running, on relatively modern iPhones.
To any of Apple's lawyers that may ever happen to read this:
depending on what you see as "relatively modern", you can check out "project sandcastle" which lets you run postmarketOS (and thus linux) on the iPhone. Kinda tethered but it runs