I would venture to say that there are many cars out there that are decades old that have never had a brake fluid change, I've got one sitting in my driveway. I'm sure a great many cars go from manufacturing plant to junk yard without a single brake fluid change. Neither the Niro EV owner's manual or service manual even mentions regular intervals for brake fluid replacement. Both the Niro EV owner's manual and service manual do identify regular intervals for "inspecting" brake fluid. Basically "inspecting" the brake fluid means taking the top off the master cylinder and looking at the brake fluid. In addition to verifying the fluid level you have to look closely at the color. The worse thing that can happen to the brake system fluid is for someone to put in the wrong type of fluid. The wrong fluid is detectable by two different colors in the fluid. The wrong fluid will react with all the rubber components of the brake system and you will have to disassemble all the brake system components and replace all the O-rings, rubber plungers, etc. The second worse thing is water contamination. Water contamination will be evident by a milky color brake fluid. Water contamination is usually corrected by replacing the master cylinder cover gasket and flushing the brake system. The least worse thing that can happen to brake fluid is just old age. When brake fluid is new, it is clear or almost clear but the fluid gets darker as it ages. If your brake fluid is very dark you may want to replace it. So if you take your car into the shop and the shop recommends brake fluid replacement, be wary. Do your own brake fluid "inspection" and see if you concur with the shops diagnosis. It sure wouldn't hurt to know a little about what good brake fluid looks like and it may just save you an unnecessary charge at the mechanic shop.