I suppose that could be good for someone with naturally soft water who wants to mash a darker beer without adjusting their water, but the majority of people in the world are blessed with hard water so we need the acid in our mash.
As a big fan of roasted malt bitterness I look at such suggestions, like no or low boil extract beers, to be nothing more than people coming up with different ways just to be different to keep people listening or reading. Seriously, how much talking about beer is there to do without going extremely scientific and losing audience because of that?
I never heard that about Irish Moss, only that it helps coagulate proteins.