I have several friends with lowered trucks, and used to have one myself, an 02 Silverado lowered 4(Upper and lower arms)/6 (flip kit and notch). With helper springs on the back (only on for short time though to an extent since sold it not long after installing, since wanted a diesel at that time), never had an issue with a normal sized load for a 1/2 ton.
And one before getting new rims, but had about 600 pounds worth of construction gear, tools, etc. under the toneu cover and couldn't even know. Didn't have much pressure in helpers either.
with helper bags on a lowered suspension, or with an air bag suspension, a truck is still capable of hauling or taking a load.
one of the other safety people at work has a 94 chevy 2500 that's lowered 3/4, and with helper bags in the rear he takes his 37' 5th wheel out all the time camping with his wife.
Believe it or not, even lowered trucks are still capable of being a work truck.