Can you explain what you mean? Letter generation etc is still usefull, I don't see what billing has to do with it. They can still charge what they want to.
I think he means pricing schemes are more simple when you go with a flat "200$/hour rate". Obviously it's shit for the client since they have no idea how many hours will be spent on the case, but that's not the lawyer's problem.
Sure. The purpose of a SaaS product would be to improve efficiency and save time. Given lawyers typically charge by the hour, they would lose money unless they could bill their clients directly for the use of the more efficient software to make up for the lost revenue due to saved time. However billing clients for legal software is not the norm.