Apologies for the length in post:
Aside from it being more of an industry term I do think that it could be more easily described to the general public when booking flights. I mean you don't have to go in-depth and all but at least with SWA they verbalize it a bit better at least IMO. Now if someone choose to ignore the information being provided to them well can't help that part.
If I choose to filter by Direct flights (which SWA tells me that means no plane change but stops) I'm only shown flights that have no plane change and they verbalize no plane change. If I choose to filter by non-stop I'm only shown flights that do not contain any stops.
No filters (just the top half of the page posted to give you the gist):
View attachment 247199
Nonstop filter:
View attachment 247200
Direct filter:
View attachment 247201
As far as day to day conversations maybe if airlines did spell it out more like SWA it might somewhat help clear the confusion but that would take people flying enough to get that.