a world without copyright means those with the largest advertising budgets will reap nearly all the rewards from new IP created by small artists. BigCorp Inc. can just sit around and wait for talented musicians to post something interesting on soundcloud, for example, then just have their in-house people copy it and push it out to radio and streaming platforms via their massive ad budgets and favorable relationships for getting new material onto the waves immediately. meanwhile the original artist gets nothing.
the position of advocating against all copyright protections at all only makes sense for people who are already wealthy enough that they don't need proceeds from their art to survive.