I get it...I've never been the maintainer of a codebase that's deployed on trillions of devices, and backwards compatibility is something to be taken seriously and responsibly when you're that prolific. I do not begrudge SQLite or any large projects when they make decisions in service to that.
However
It always makes me feel oddly icky when known bugs (particularly of the footgun variety) become the new standard that the project intentionally upholds.
One thing you should do is grab your data for easy moving, you haven't already.
Assuming you're using the default Lemmy web UI (not Voyager, or Photon, or a mobile app, or whatever), click on your username in the top right, and select "Settings".
On the settings page, there's a section called "Import/Export Settings". Click the "Export" button and let your browser download the file.
Then, when you switch instances, you can go into the same Settings page on the new instance, select the file you downloaded, and hit "Import" and you will automatically be resubscribed to the communities you subscribed to.