When did that start?
The comment section used to stay exactly the same even if you came back years later but now some comments just disappear.

Is it to use less storage or just to police the tone of the conversation?
It just seems weird. Even if it's just a small unimportant part to me youtube comment sections are like history. So it's sad that they're being amended without any input from the actual people who wrote them. Don't get me wrong some of my own comments from the past, I'll delete them myself, but some get deleted that I wouldn't delete.
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