It is a good time to point out why and how he uses them. They are best used as a gig/recording tool."If markers are good enough for Edgar Meyer..."
Edgar has high end responsibilities where starting on any number of pitches is required and there may not a be a second take or try. Having them get you through a concert or recording is a fine use of them. Us bass players are VERY often in over our heads.
Using them for practice is absolute folly. When you can't play in tune, it really doesn't matter until you can. Forcing the issue with tuners and dots just delays actually learning the instrument.
Teachers who use them are just being lazy and either want to rush getting an orchestra or band together or not have to hear an out of tune student. It is about them and not the student.
So, it is really about when to say when.
I would say dots are for advanced players with advanced responsibilities.