What is interesting to know is what happens after this version. If next release (Nextcloud 23) uses a different method and to make it work is not just apply a line, we are out of options. As far as I know, Gallery or other featured applications do not cover this scenario.
For me, this would be a ‘move out’ Nextcloud reason; if anyone gets any update and could post it I would appreciate.
We have to differentiate between the app not working and the app not being able to be installed or activated.
The first works for me without any problems.
The second also works without problems and changes on any xml files, because Nextcloud now officially allows “untested apps” to be installed and activated from the GUI.
Of course, it can happen that a certain app still does not work as expected, because it is indeed not compatible. But this is definitely not the case with the Preview Generator app. For me, it runs without any problems on Nextcloud 22.2.0 with PHP 7.4.
I doubt that you won’t be able to install it somehow. But if it were to become incompatible at some point for reasons other than the version check, then it would be a problem if the app were no longer developed.
Changing supported version in app info file is a quick little hack I (need to) use for few years now, specially for E2EE app which also is 3 months behind new major NC version. But that’s nothing a „normal“ user should be forced to do.
New major releases of NC are being pushed out way faster than app maintainer can keep up on. This specific preview generator app solves a problem the bare metal NC never took care of - and therefore is essential to many users out there. I’d vote for integrating it into core, but at the end I‘m fine with any maintainer (continued as separate app).