On one hand, you can claim that YouTube is being proactive against what they perceive to be a problem and that's something.
On the other hand, they don't choose to be proactive against copyrighted material - they just comply with the law when the law comes knocking and that's that. It simply doesn't make sense for them to allow the law to do its job in one place and then be overly proactive in another. At the very least, it undermines their argument that they're only doing this to comply with the law. They're not. They actively want to censor material that they don't agree with and they'll use whatever excuse they need to do it.
On the other hand, they don't choose to be proactive against copyrighted material - they just comply with the law when the law comes knocking and that's that. It simply doesn't make sense for them to allow the law to do its job in one place and then be overly proactive in another. At the very least, it undermines their argument that they're only doing this to comply with the law. They're not. They actively want to censor material that they don't agree with and they'll use whatever excuse they need to do it.