YouTube Domain Redirection to Local Server Not Working in Browser, but Successful via Command Line

Redirecting to a page does not work with HTTPS, as the client browser will treat the missing or incorrect certificate as an error and never render the page.

For that very reason, with growing proliferation of HTTPS, being almost ubiquous today, Pi-hole has long switched to NULL-blocking as default, and support for the block page was finally dropped about two years ago.