When I first started teaching, I would take my class into the retail section of the store to talk about the different options in choosing gear. When I came to the wall covered with mask options, I talked about the difference between high volume and low volume masks. As with all gear, I tried to talk about pros and cons of each choice, but I struggled to come up with a good reason to buy a high volume mask. Simply having students try one of each to see the difference in range of vision was enough to convince them.
I can't do that any more. The mask wall does not have any high volume options on display. I think that you can't buy a high volume mask where I work says a lot about the direction that gear makers are going with this, and there must be a reason.