Nitpicking, but I'm not sure that it was ads that killed dash sat navs. At least in my experience, they never really developed to that point where car companies would put ads in.

It was more that they were expensive options to install, a pain to keep updated, and generally weren't all that good.

Even before the live traffic and automatic detour features, phones didn't cost money to keep the onboard maps up to date, and you already had one, so you didn't need to either buy an add-on, or get a special unit for it.

With android CarPlay and Apple Auto, you could just put your phone map on the screen, which was basically the same thing, but a cheaper equivalent, since the hardware was on your phone instead.