Cached function in layout and page runs twice

Docs here state that:

You can use React cache to memoize data requests during a React render pass. For example, although the getItem function is called in both layout and page, only one query will be made to the database:

But on this Sandbox, you can see in the logs that it gets called twice.

Tested in both Vercel deployment and locally.

To Reproduce

  1. Open the sandbox above
  2. Clear the terminal
  3. Check the logs
  4. Refresh the embedded browser
  5. getItem will be logged twice

Provide environment information

Operating System:
  Platform: linux
  Arch: x64
  Version: #1 SMP PREEMPT_DYNAMIC Sun Aug  6 20:05:33 UTC 2023
Binaries:
  Node: 20.12.0
  npm: 10.5.0
  Yarn: 1.22.19
  pnpm: 8.15.6
Relevant Packages:
  next: 14.1.0
  eslint-config-next: 14.1.0
  react: 18.2.0
  react-dom: 18.2.0
  typescript: 5.3.3
Next.js Config:
  output: N/A