The goal: I would like to create a video of a route, as it would appear if one could smoothly trace through the entire route in Google Street View. (See an example of the previous solution using Google Street View Player (GSVP).
In Google Maps, it is only necessary to designate starting and ending point, not trace along each step of the route. Unfortunately, without GSVP, there doesn't seem to be a way to create the desired route video in Google Maps anymore.
I didn't see a way to export a KML from Google Maps, so I used Google's My Maps to sketch out a route, and exported that route as KML. Then I imported the KML into Google Earth Pro (GEP). Now, in GEP, I am looking at the territory in question, with a nice blue line across it, signifying the desired route.
What I'm missing is a way to persuade GEP to treat that blue line as a path to be followed in a video tour in GEP's Street View. I'm thinking this would give me an alternative to the GSVP output.
Possibly it just won't work that way. In that case, I welcome alternate suggestions for achieving the goal.