Since this is a symptom of a bigger issue that isn't being fixed, give us an option in server properties to suppress duplicate entity warnings. I've had this error for so long and I've never experienced an in world issue. just the console SPAM so let us turn it off.
Confirmed for 1.18.1. Server and player are on high speed connections
view-distance=16
[02:51:23] [Server thread/INFO]: Skipping update from removed player 'adj['real_bendi'/2738705, l='ServerLevel[world]', x=106.30, y=95.94, z=-124.33, removed=KILLED]'
[02:51:24] [Server thread/INFO]: Skipping update from removed player 'adj['real_bendi'/2738705, l='ServerLevel[world]', x=106.30, y=95.94, z=-124.33, removed=KILLED]'
[02:51:25] [Server thread/INFO]: Skipping update from removed player 'adj['real_bendi'/2738705, l='ServerLevel[world]', x=106.30, y=95.94, z=-124.33, removed=KILLED]'