It's happened with so many businesses.
Maybe the solution here is to stop supporting new phones with old versions. So your app works forever but if you upgrade your phone you have to buy the software again. It's hard to find what feels fair.
In the old days, you'd buy a new version of Mac or Windows or any software that you run on it (Office, Parallels, etc.) when you wanted the new features each year.
I think Apple's App Store has a lot to do with why everything is now subscription-based. They used to offer developers a smaller Apple-commission (15%) for subscription sales instead of the typical 30% for in-app purchase sales and paid-apps.
This was great for businesses, but in my opinion, only service businesses should be subscriptions - this transition would help reduce subscription fatigue. Normal software should mostly go back to just issuing new versions each year (or whatever frequency), so that consumers re-frame the purchase cycle to something that feels more reasonable again.
In order for this to occur, however, Apple may need to adjust the App Store algorithms. If you were to launch a new app (ex. "Kino v6"), you'd start all over again from day 1 with 0 app ratings and reviews, and not rank well on any keywords nor in the top apps charts.
Some apps simply rename their app with each new version, but that introduces similar complexities, especially for users who already paid & downloaded the previous "version". So in a big way, the App Store de-incentivizes any kind of transition away from a subscription-based business model.
The "new versions" business model vs. subscription may be similar cost to consumer (it wouldn't support monthly users), but it would allow consumers to only update when their ready and could continue using an old app version (especially on older devices) as long as they'd like. If a customer really likes the software, they'd likely buy the new version to access new features & device support before too long anyhow
One way which feels fair that I have seen companies do is provide "Maintenance".
Premium paid support offerings which also includes upgrades to any versions released during your contract duration. It's enterprisey, and maybe weird for a camera app (how much support could you possibly really need?).
[0]: http://web.archive.org/web/20111130073123/http://www.filmicp...
[1]: https://www.cined.com/filmic-pro-is-joining-forces-with-bend...
[2]: https://www.theverge.com/2023/12/3/23986187/filmic-staff-lai...