Features for the note taking app detailed in this guide include:
- Self-hosted
- Private
- Built to last
- Low maintenance
- Access in one place & from any device (Obsidian charges for this feature)
- Versioning
- Zero vendor lock-in
- Extendable (eg. passing text-embedded notes to AI)
Looks like https://docs.numerique.gouv.fr/home/ except that one is backed by two governments.