It'll take a good amount of effort to change people's minds about sprawl, but I'd really abandon the "15 minute city" phrase purely because of the WEF association. It's automatically a non-starter with these people because of that.

I have successfully convinced conservatives, all manner of sprawl dweller and even West Virginian bootleggers, but it's not going to happen if you're using any of the same terms as WEF. I'm sure that particular person is too far gone, but most people are amenable to not risking their lives on dangerous roads just to feed themselves, honestly most people aren't this stupid.

By the by: The biggest sticking point is always the association between denser areas and crime, but you just have to lay out the Fair Housing Admin, red-lining, how the reduction in services preventing strife was purposeful to drive white flight (and that money went right into loans to municipalities along highways to build sprawl), how it was done to isolate people in sprawl so they'd work on the war machines to pay their mortgage and get all their info from the television. It was a subsidy to make people more conservative, to beat the Soviets and prevent revolution at home by physically and socially dividing people, but it was never sustainable. These people are very skeptical of "government" and you can appeal to their sense of tradition - cars are relatively new, and the infrastructure is clearly breaking down and requiring trillion dollar bailouts just to be kept hobbling along, not to mention public sewer/water.