Having briefly looked into the code the other day given the freezing Electron sandbox issues, I don’t get the impression that this flag substantially changes how shared memory works, merely just the location of the file. If this shared memory is backed by the hard disks then it’s inferior, but when I was testing it, it picked $XDG_RUNTIME_DIR, which is the same kind of tmpfs as /dev/shm on classic and hence I’d presume also on Core?
Obviously not an expert here but at a glance I don’t think this is a hacky approach as long as the directory it picks is backed by RAM.