There has to be a good reason why psychological warfare is used, including by the United States in periods like the Vietnam War. The expectation is that statements written on paper or recited through loudspeakers or similar influence people's thoughts, which influences what actions they will take. Those actions are supposed to be beneficial to the forces scattering them from a helicopter or posting them on walls. They're trying to get you to do something regardless of what your preexisting thoughts are beforehand.

Now tear down the pieces of propaganda and burn them. Is this censorship?

I think human brains are sufficiently able to be hacked by the right information. With certain kinds of information, those people could end up causing material harm to someone who is completely uninvolved. That is the ultimate danger that I believe YouTube and the like are trying to avoid, and if true it would be an admittance of a sort that some kinds of information are dangerous to some kinds of people. The name "psychological warfare" implies that communication can be weaponized, in a sense. Certain people do not change their ways regardless of what you try to tell them.

I think the issue is centered not around people trying to have a reasoned debate, but those who have been lost to debate more or less permanently. Previously, you couldn't scatter this kind of information about on the scale were seeing today, and also recommend similar content using very effective algorithms. The more millions of people the content reaches, the more latent believers it will reach and end up converting, even if the conversion rate is a fraction of a percent. And many of these people are very vocal.

In a sense, the content takedown seems like an attempt to counteract the fact that the algorithms are too effective of a medium for misinformation. I don't think we would have seen this kind of scale with books or flyers.