Could be related but tailscale is specifically UDP and not TCP so similar problems with offloading but a different datapath. Could just be that the whole off the offloading featureset is somewhat broken in some NIC combinations.
See the bug, I can reproduce this on Broadcom and Intel NICs as well so I think its a wider problem. The problem exists when newer linux kernel features in 6.16+ interact with new Qemu versions 11.0+ which introduce new offloading scenarios. I don't know why these break if its a problem in Qemu or the host Kernel though.