I wrote about this a few years ago.[0] The gist to avoiding premature over-architecting is to keep sticking with as static/hardcoded behavior as possible to meet the requirements. Just make sure it’s well organized and cleanly written in your language of choice. Then over time add configurability to that behavior as specs change. Architecture is easy to change not when it correctly predicts future change (almost impossible), but when it is straightforward enough to follow and reshape.

In my experience, keeping behavior static/hardcoded is the architectural equivalent of avoiding premature optimization.

[0]: https://max.engineer/cms-trap