I don't think there are perfect answers here. Someone might use the same IP address of a bad actor (e.g. they share a VPN provider). One person may use the provider to watch Netflix, another person may use it to hide their identity to do bad things.
From my limited experience in this space (I moderate a tiny social app that has problems with bad actors), IP address blocking had high false positives and low false negatives.
Even back then using IP address only wasn’t how we profiled. If the poster meant literally basing this on IP only, then yeah, I sort of agree.
But a false positive here just means someone can access the video who isn’t supposed to access it. Without the system in place anyone can access it.
In the case of trying to block a specific video, it could be even more effective, because as soon as that video gets uploaded, you can assume the 'new' person is the same person as the existing profile—it doesn't really matter if you're wrong because even if it's two people, you're trying to stop them both.
I'm not sure how this would in any way inhibit journalists or activists except that, they too, would not be able to upload the disallowed video to your site.