Its main goal is to reduce the number of WordPress installs running on unsupported PHP versions through education, awareness, and tools to help users update their site's PHP versions.

The biggest motivator for hosts would be if WP would quit acting like it's a tiny little OSS project and simply say "In X months/with the release of version Y we will no longer support PHP less than 5.6. As PHP versions become unsupported, we will deprecate support for those versions after 12 months."

But no... they will utterly change how endusers have to edit content but god forbid they upset hosts....