WiFi was off when try lan connection.
But anyway I think we have a solution.
After a reset (windows restore) everything was fine for a few days, then issues again. Some more fiddling and it *seems* that the settings that fixed it was disabling “large send offload packet”. This is under device manager> network> network card (not WiFi adapter). For now this seems to solved the issue.
What is odd is that apparently any new network card should support this. No idea but seems to be a common ish windows 11 issue.