There are several software products I want nobody will build.
For example, I want a “screen saver” that will randomly select from a collection of video and still images and display them across multiple screens.
Pretty much like Apple’s annoying  screen saver, but for video it would randomly select a xx second file segment and play that without sound.
I don’t think anyone will ever build this. It’s too hard to do  and there’s no money in it. Only a small number of people would pay, say, $20 for this. Maybe 1 in a 1000. After expenses and marketing it would be hard to earn even a few thousand dollars.
Which reminds us of the false promise of The Long Tail. Those were the days that Netflix had a huge catalogue of barely viewed movies  that were often very fine. We thought there would be business for the interests of the 0.1%. That didn’t happen.
This is why I’ve given up on trying to predict the future ...
 Whenever macOS cannot connect to the folder hosted on my NAS it reverts to the default collection. I need to restore my share and I’ve never been able to find an automated way to do that. On iOS things are much worse. Speaking of products I want, I’d pay $20 for a macOS utility that that simply reset my screen saver to my preferred share.
 We never thought software development would keep getting harder. We used to think there would be a set of composable tools we could all use (OpenDoc, AppleScript, etc). We expected a much more advanced version of what we had on DOS or Unix in the 80s or the early 90s web. Instead we got AngularJS.
 In the mailer days our kids movies were unplayable due to disc damage about half the time. Finally gave up on that.