That’s an exaggeration. YouTube is still far more accessible than network television even if brand new accounts aren’t able to livestream to huge audiences.
Limiting new accounts is a common, and often necessary, feature in most internet platforms. Even HN will limit how fast new accounts can post and highlights new users in green.
If HN allowed new users to sign up and immediately post hundreds of comments or links, it would be inundated with spam and abuse. Likewise, YouTube requires new accounts to demonstrate some actual traction before they’re allowed to livestream to huge audiences because the feature was being used for abuse.