"but DW is asking me if it's just another gadget or if RVers find them essential, useful, or just another gadget"
Inform DW that without them it will be her job to dig out boards or blocks and position them, potentially in the dark or rain while you drive onto them....that will likely answer her question
2013 Newmar BayStar Sport 2901
5 Star Tune, EEZ TPMS
Toad: 2018 Corolla IM 6 speed, Roadmaster Tow Equipment