The last_lts_mongos_commands.js & last_lts_mongod_commands.js files contain the list of commands added/removed on the router since the last LTS release.
These files were not properly sanitized once v5.0 branched out. Therefore, we must revisit them and ensure all commands on the lists were added/removed after v5.0; we can eliminate those commands that were added/removed either before v5.0 or on v5.0.X.
I recommend removing all the commands that are already in the last_lts_mongos_commands.js & last_lts_mongod_commands.js files in v5.0.