I am glad you are happy with 30/50 pressure. Most people are not or I would not be in business. 40/60 is the most common setting these days, and people still complain about that. With any filters you lose pressure, and many houses are plumbed with pipe that is too small. And some of those small pex lines have insert fittings which further restricts the pressure. If you are at the bottom of the hill, don't have any filters, and have large pipes all the way to the shower, 30/50 might be fine. But I can assure you people moving to the country from the city would not be happy with 30/50 pressure.
When the house is on a hill, has multiple filters, or has long or too small pipe lines, much higher pressures are needed. I did several today that were 60/80 and one that was 120/140 as those houses are considerable higher in elevation than the well and pump.