I wouldn't sweat that minimum too much. That's so the manufacturer doesn't get sued by someone weighing twice your weight. I rode a 700 x 38c Pasela last weekend down a few thousand feet of gnarly gravel. Steep. wild wash board, big rocks. Left the house for the opening 35 miles of pavement with 40 psi, then kept dropping it for the gravel. Didn't have a gauge but I was certainly under 30 psi. Back on pavement, it felt flat and glues ti the road. (Your 2.1 = 53c or 40% larger than my tire. I weigh 150 so you outweigh me by 20%. You should be able to go very low (like very low 20s) with no issues at all.)

Ben