Running a drip system should not lead to a reduction in filter maintenance at all, quite the opposite actually. When running a drip it is important to pay closer attention to filter maintenance. Detritus/waste buildup in the filter system will be harder to detect via water testing with the constant dilution from the drip.
I know many swear by a drip system and claim they never do water changes, but a drip does not remove things from the water column in the same manner a 30-50% water change does.
Drip systems should be thought of more as a parameter stabilizer or dilution system to aid with periods of heavy feeding.
Filter systems like many run on the forums (total system volume below 1,000 gal) may get away with drip only/no water changes for a few years. Down the road as rays grow and feeding requirements increase they will most likely run into issues like disease/parasites/sudden "unexplained" deaths. UV's at the proper dosage can help reduce pathogens in the water column and give you more time, but proper sized filtration system and maintenance are critical.
On stocked tanks/systems that have been running for 3-5+ years just look at the buildup inside the plumbing components alone. Having clean-outs on overflows and access to other sections of plumbing to clean is very important maintenance as well in the long term.
Unless you are running a massive system with appropriate sized filtration manual water changes are still important.
