Deploy pages to a subdirectory

Sometimes it is useful to deploy a site to a subdirectory.
For example, documentation portal can be under
There are multiple reasons why would someone want to do that, but I think mainly it’s useful when such sub-site is built using a different technology stack, and it had to be in a subdirectory because of SEO considerations.
Deploying to a subdirectory is easily achievable using workers-site. However, in pages this feature is missing.
I’d be happy to see this available in pages as well.