Your first issue of print flatness can be easily overcome by cranking the heat on your print dryer (I am assuming you have a drum/canvas type), placing the prints face up in a stack and tightening it down. Turn off the heat and let them cool in the dryer. I have been doing this for many years, and it works. To keep them flat over the long term, I overstuff paper boxes so when I stack them the prints carry the weight and not the box. This method keeps them flat as a pancake.

If you want to keep it simple, I would suggest getting a box that is nice and putting the flattened loose prints in it with some gloves. Black portfolio boxes are nice and not expensive. An aluminum box would be a little nicer. You can find them both at the usual sources for archival supplies, or your local art store.

Personally, I only mount prints when I have to. Showing prints to friends does not qualify. Even when showing prints to serious people, I will still show loose prints. I print pretty small though. If your prints are large you need to mount them to protect them, or at least handle them yourself. Everyone has their own thing though. For some people the presentation is part of the work.

One problem with a traditional medium like darkroom prints is people tend to think there is only one way to make and present them since mounting and matting has been done forever. ROLs methods may work for him but aren't necessarily a universal truth. I don't think calling someone's efforts or choices vulgar does anyone any favors. One example that contradicts his approach is Masao Yamamoto, one of the most successful artists today. Take a look at how he does it. Hardly vulgar/hardly amateurish. As the French say, chacun a ses goŁts.