Sorry, I didn't realise you were the only one allowed to ask for further details on the OP
Correct or not, I still haven't seen any evidence to support your contention about the potential liability of DMs in these circumstances - just a lot of opinion (both for and against). So you'll have to forgive me if I don't change my mind just because you say I should, even though you are an instructor and claim to have done more boat dives than me
On the topic of my alleged 'complacency' I think you're confusing my opinion on responsibility with my personal attitude towards dive safety, both for myself and for the divers that are under my care when I'm working as a DMiT or guide (no, I don't 'set their gear up' for them, but I do try & check that they have their air, masks & fins on before they splash)
FYI this approach to argument is known as ad hominem tu quoque FYI, not to be confused with ad hominem abusive or ad hominem circumstantial
You can look them up in the link I provided to you earlier