EDIT: This impacts 6.3.11_p1, which is in official Funtoo – so this isn't just a harvester thing.

With debian-sources-6.4.4_p2 (in harvester/2023-08), I am experiencing identical symptoms to what was reported in FL-10937, which impacted late 5.18 series debian-sources kernels.

The symptoms are identical – up to 1000ms ping times for sites that should be in the ~20ms range, and general network flakiness and slowness.

debian-sources-6.3.7_p1 does not have this issue, so this seems like a very recent regression.