Actually I think this just stems from simple economics.
Monetization under online content-ID schemes (including relatedly serving takedowns under DCMA where required) all require the content usage rights to unambiguously be established AND verifiable in an automated fashion. Before an ad can be placed on a piece of content or served a DCMA takedown, the right to do so needs to be veirfied (eg. DCMA requires "good faith effort"), or they may get conter-sued.
With normal licenced content, that is easy to determine in an automated fashion - audio signatures will identify the potentially infringing content & then possibly some algorithms will check for fair-use - eg. length of the original song used, audio quality to eg. indicate it it's a production video or you recording your kid dancing, maybe even a human in the loop at the very end.
With CC licensed content, every piece of potentially infriging content needs to be human verified for usage rights & even then it may not be clear quickly. It is too expensive to hire an army of humans - so you would not support it at all.
Monetization under online content-ID schemes (including relatedly serving takedowns under DCMA where required) all require the content usage rights to unambiguously be established AND verifiable in an automated fashion. Before an ad can be placed on a piece of content or served a DCMA takedown, the right to do so needs to be veirfied (eg. DCMA requires "good faith effort"), or they may get conter-sued.
With normal licenced content, that is easy to determine in an automated fashion - audio signatures will identify the potentially infringing content & then possibly some algorithms will check for fair-use - eg. length of the original song used, audio quality to eg. indicate it it's a production video or you recording your kid dancing, maybe even a human in the loop at the very end.
With CC licensed content, every piece of potentially infriging content needs to be human verified for usage rights & even then it may not be clear quickly. It is too expensive to hire an army of humans - so you would not support it at all.