No, it doesn't affect the non-subscribing users. They will see ads either way. It is the artists and the subscribers who would be adversely affected by artists that do not participate.
It is the artists ... who would be adversely affected by artists that do not participate.
Adverse affects for independent artists who do not sign up translate to adverse affects for non-subscribers that want to watch those artists on YouTube.
Adverse affects for independent artists who do not sign up translate to adverse affects for non-subscribers that want to watch those artists on YouTube.