Occasional desync when trying to enter/exit a boat while the server is lagging

When entering a boat when sitting in another boat while the server is lagging, it is possible that a client-server-desync occurs, where the client is outside of the boat while the server still considers the player to be inside of it.

To reproduce

1. Place a lot of boats in the same place (e.g. activate a repeating command block with the command summon boat ~ ~0.5 ~ for a second)
2. Cause server lag, e.g. by setting /gamerule randomTickSpeed to a high number (mspt should be above 50)
3. Right-click the boats repeatedly until you are no longer able to enter them
   → Desync
4. Walk away
5. Try to place a block
   → It disappears
6. Press shift
   → You're teleported back to the boats