As part of being locked, locked users cannot PM anyone except for members of global staff. However, the restriction extends to bots. Because there is not a user behind the bot (hence it being a bot), there is no risk for locked users to further harass users. The only thing I can think of is Monita mail. The rest of everything you can do (ex, checking the top rank in the Tournaments room) with a bot does not involve another person. Locked users should be able to talk to global bots.
