Which seems reasonable. And those who care deeply will have no problem configuring it the specific way they want on their own project. Win-win.

Unless you don't know it exists of course

Well no, the software should be configured in its best state by default. Otherwise you run into the case where the user has to read the documentation like a legal contract to find all the footguns that need disabling. If STRICT is strictly better, than that should be the default. The correct approach here would be for the user to pass along a "compatibility version" tag when first connecting, which would set the defaults to whatever was default in that version. That should be something you force each user to set in their source and it should never ever have a "latest" value. It may be too late for sqlite, but if I were designing an API that had to remain stable for decades now, I would put an enum with possible versions in a header and require the user to pick one.