Starting a new rails app on osx ruby 3.0.2/rails 7.0.0.rc1 I'm getting the same error as Douglas mentioned: 

The asset "application.css" is not present in the asset pipeline.
<%= stylesheet_link_tag "application", "data-turbo-track": "reload" %>

Unfortunatly there is no automatic asset compiling active and rails assets:precompile failed. Any other hint from your side to fix this issue?