SQLite is more tested (as in code tests) than most other databases. Its downside is that you can essentially only use it from one app at a time, and not over a network.
Also, it is safer than writing to your own files. It has tests for probably all the ways that writing to files can break. So if local state needs to be maintained/changed and written to disk it is great. https://www.sqlite.org/testing.html
Subiekt 4 is based on FoxPro database, it can be used over network simply by mounting SMB network share.
Just click "Share this folder" in Windows and run the same executable on another computer.
Indeed, I was responding to GP's assertion that SQLite is only for data you don't care about.