If it doesn’t work on a certain phone then dont show it as available for that phone. Simples….
Also for instance, when I try to install certain apps on the Early 2011 MacBook Pro that I use, there are some apps that have a block/stop icon on the bottom-right of the app icon itself that indicates that it is either not compatible or would not run the the device (It's good start).
But IMO, What Apple is doing is great and it has something to do with Security and Privacy to some extent. Imagine, there is one app has not been downloaded at all or have few downloads for the course of 12 Months for the past 3 years feels like it's a shady app waiting for a victim.