Not saying CS wouldn’t benefit from something like this but just pointing out another resource that I’ve used for something similar. If anything maybe it could be used as inspiration on designing CS’s version?
http://www.jonathanokeeffe.com/strava/map.php
Personally I used it to display all my runs & rides onto a single map but you could filter to just runs if desired. Then ran the query and recorded using QuickTime on my computer. Posted to YouTube (Run / Bike SF Streets - YouTube)
A problem I could foresee and was a problem with my above method, is that most city projects are over a long time span (months or years). This means to show progress you’d need a semi lengthy recording as well. GIFs are really only meant lengths of a couple seconds. Videos can be how ever long you want but it takes processing power to encode and build the videos. Plus storage size/costs skyrocket once high-quality videos are created. These aren’t problems that couldn’t be overcome (especially if they are not stored long term on CS servers but rather on social media platforms as you mention) but they are things James would have to work out.