Since I don't download uncompressed 4k video anymore, I'm personally getting practically all of the value of the internet (to me) from merely having a cheap cable connection at home. I've never been certain who 5g or fiber is really targeting. Amazon works fine, Netflix works fine, downloading an OS or language tool set isn't too heinous. High data speed to a phone is uninteresting, but YMMV. As usual, improvements become less useful on the margin.

The one use case I've run into might be robot cars, probably lower latency/higher bandwidth. I don't know enough about where the intelligence actually lives or how much in the way of inter-car communications is actually required though.