Watchlists -- can this functionality be disabled?

Is it possible to turn off the functionality for watch lists?

None of my users actually USE watch lists … I have elderly and young users who also don’t really understand what they are.

Turning off the My Lists main menu item would be very useful for people who don;t use it — given it’s such prominent place in the UI.

… option for disabling the add to watch list functions though-out would be good too.