Your approach to settings configuration should match your theme’s intended use. There’s no one-size-fits-all strategy for block theme development.
For widely distributed themes like Twenty Twenty-Four, you want to provide useful customization options while ensuring everything works together. Include theme-specific color palettes and font sizes, but remove WordPress defaults that don’t fit your design.
For client projects, the opposite approach often works better: lock everything down by default, then selectively enable only what specific users need access to. This prevents clients from accidentally breaking carefully-crafted designs.
The key lesson? Always use theme.json to control settings – never ship a block theme without it. WordPress Core provides extensive customization options by default, and you need theme.json to curate that experience appropriately for your specific use case.