Photoshop (and maybe all Adobe apps) need a setup option (preference) to display a dialog to set Windows File Associations for file types applicable to Photoshop. This would bring Photoshop up to a par with many other apps that already do this. The typical function in other apps allows you to either set the association back to it, or just leave it alone.
Another extremely typical option on the dialog should be to check all of the check-marked file associations at app startup, and reset them back to Photoshop if they've been directed elsewhere.
There are several reasons I know of why setting file associations only at the initial install isn't enough:
1) There are a slew of cheap specific photo apps available as well as some well known apps that set many graphics file associations to themselves at install. Often they don't inform you. Once you realize this has happened, it's quite intensive to set them back to Photoshop. Especially when you don't already know how to do it. Even if you uninstall these apps, they don't set the associations back to Photoshop after uninstalling.
2) Search the web for problems with adobe file associations and you will find that problems occur. It's extremely unprofessional and user-unfriendly to recommend re-installing. Even though I saw a comment that Adobe dev team wasn't able to re-produce an multiversion install/uninstall situation causing file association problems, they still happen and it's extremely frustrating especially when you're a graphics artist and not a Windows Tech.
3) Windows 10 upgrades your system without having to re-install anything. But it includes little apps that handle various graphic file types. Some of those apps steal the file associations without telling you.. See # 1)...
It's just user-unfriendly not to include something in Photoshop to select which file types to associate back to Photoshop (or CS suite apps). If this is only a windows issue (not familiar with iOS...) then maybe a separate Photoshop utility or suite utility could be supplied (or even available from support downloads). Though it would really need to detect and allow selection of which installed version of Photoshop should be associated with the file if multiple versions are installed...
Photoshop is just simply lacking OS support if you supply no easy way to fix this problem.