The problem with hardcoded pages
A hardcoded page puts layout and copy in the same file. It works for one page. It gets messy at ten. Every copy change means editing a component, and every layout change means scrolling past paragraphs of text to find the markup.
What content collections change
Content collections move the copy out of the component. The route renders layout. The content lives in JSON or Markdown. Editing copy means editing a data file, not a component.
- Routes stay small. A page file reads data and renders.
- Content stays editable. JSON and Markdown are readable without a build step.
- Schema stays explicit. Frontmatter defines what each entry needs.
When a CMS makes sense
If the person editing content is not comfortable with files, a CMS like Decap can sit on top of the same collections. The content model does not change. Only the editing interface does.
Summary
Content collections are not a framework feature you add later. They are a structural choice. Make it early and the site stays readable as it grows.