Specifically it decrements the TTL of routed packets, so hotspot traffic will tend to have a TTL of 63 instead of 64. You could theoretically disable this at the risk of creating infinite routing loops, although android probably makes it inaccessible if the kernel has a setting for it at all, so you might have to rewrite packets in user space.
It has been a long time since I've done this, but:
If your Android is rooted, it's pretty easy to get tethering working. There's magisk modules that can fix the TTL problem and/or disable the hidden carrier-installed software that Android will ask for permission before enabling tethering.
