If rolled out widely, this would make web browsers and third-party YouTube clients without a DRM license unusable for YouTube playback, download, etc. This would include almost all open-source web browsers and almost all third-party YouTube clients. Archive link to reddit post about this
Considering how minimal income on YouTube actually is, I don’t know if that’s actually the main obstacle. There’s a reason why even some big content creators have Patreon/Locals.