In reply to John Teague.

Educating users about the benefit of PHP 7 will go along way to getting versions switched to that.
That is right, and does WP do anything for that? No. They were kept telling that a screen telling one should upgrade would be annoying for the users (naturally if they just do not know the risks of EOL PHP versions like 5.2 that is not annoying at all). Now Yoast’s plugin does educate people and the stats are pretty impressive. So to sum it up there is nothing bad about users who do not know some relevant information, but there is something really wrong about WP not to educate their users properly and finally a plugin has to take over that role.

In regards of apps written for older PHP versions: that is why most hosting companies offer different PHP versions and the user can switch between them with just a click. Other companies can install a different PHP version for a given folder on the server on request. All the other companies that are not willing to upgrade/give choice to their users but just get their money should simply get rid of.