next.js: On-Demand Revalidation does not revalidate when using the App Router and deployed to Vercel

Verify canary release

• I verified that the issue exists in the latest Next.js canary release

Provide environment information

Operating System:
      Platform: darwin
      Arch: arm64
      Version: Darwin Kernel Version 22.4.0: Mon Mar  6 20:59:28 PST 2023; root:xnu-8796.101.5~3/RELEASE_ARM64_T6000
    Binaries:
      Node: 18.15.0
      npm: 9.5.0
      Yarn: 1.22.19
      pnpm: 8.5.1
    Relevant packages:
      next: 13.4.5-canary.4
      eslint-config-next: N/A
      react: 18.2.0
      react-dom: 18.2.0
      typescript: 4.9.5

Which area(s) of Next.js are affected? (leave empty if unsure)

App directory (appDir: true), Middleware / Edge (API routes, runtime)

Link to the code that reproduces this issue or a replay of the bug

https://github.com/austintreneff/reproduction-app-revalidate

To Reproduce

1. Clone or manually copy the minimal reproduction created here
2. Deploy the project to Vercel (this is necessary because while running locally the issue does NOT exist)
3. Once deployed, navigate to the home page where you will see a Date (generate at build time) and a random number (fetched at build time)
4. To perform an “On-demand revalidation” navigate to the path /api/revalidate
5. You should see a 200 response confirming the validation
6. Navigate back to the home page and notice that the content has not be revalidated

Describe the Bug

When deployed to Vercel, On-demand Revalidation using the App Router and revalidatePath does not revalidate data on static paths.

When running the project locally, the revalidation correctly updates the data, but once deployed to Vercel, the data never gets updated. I have confirmed everything works fine when running locally with next build && next start

Expected Behavior

I expect the data revalidation to successfully revalidate the home page of the app.

Which browser are you using? (if relevant)

No response

How are you deploying your application? (if relevant)

Vercel