I think the problem is Shiyo wants to do camp for an hour for substandard gear, so they have something to do. I do see how the mobs being rarer adds to the excitement factor when you do see it, but in a game with a population, like ffxi was, it basically leads to 90% of the people never doing the content, and rarely at a level appropriate time. How many people fought leaping lizzy at level 11? Most people never got to fight Mee Degi the punisher.
This was a move to create content that people who were actually that level would seek, and make it so they could actually try to obtain it. trying to beat those nms, with level appropriate groups, is about on par with how good the drops are. They took down the thrill of the rare sighting, but increased the joy of trying to obtain an item you want, with a challenging fight that doesnt require you to do some inane, irrelevant other task to do it, like killing 1 bird every 5 minutes for 1-3 hours, for a 30 second fight.