According to many commenters in the linked thread, it's fixed in MacOS 13.2.1. Not great that it happened at all, but good to see that it was a software issue.
And, if it's something that's worked around in software (meaning, it was a hardware issue), that might have issues for things like Asahi Linux, which probably won't have that workaround in place.
Arguably it would impact the support for other OSes, especially alternative ones who'd need to reverse engineer the workaround and/or write their own to get the network stack working.
It could also fall apart the day Apple decides this machine is not supported anymore, and their next OS won't have the correct drivers anymore. It's their prerogative, but will sure suck for the machine owners.
PING fritz.box (192.168.1.1): 56 data bytes
64 bytes from 192.168.1.1: icmp_seq=0 ttl=64 time=11.845 ms
64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=24.287 ms
64 bytes from 192.168.1.1: icmp_seq=2 ttl=64 time=3.120 ms
64 bytes from 192.168.1.1: icmp_seq=3 ttl=64 time=2.630 ms
Request timeout for icmp_seq 4
Request timeout for icmp_seq 5
Request timeout for icmp_seq 6
64 bytes from 192.168.1.1: icmp_seq=7 ttl=64 time=0.801 ms
64 bytes from 192.168.1.1: icmp_seq=8 ttl=64 time=1.139 ms
64 bytes from 192.168.1.1: icmp_seq=9 ttl=64 time=0.772 ms
Request timeout for icmp_seq 10
Request timeout for icmp_seq 11
Request timeout for icmp_seq 12
64 bytes from 192.168.1.1: icmp_seq=13 ttl=64 time=0.784 ms
64 bytes from 192.168.1.1: icmp_seq=14 ttl=64 time=0.674 ms
The above suggestion fixes it, hopefully permanently:
settings->network-><ethernet interface>->details->hardware "change anything, safe and undo"