Did they made any changes against cryptos in their terms and policies? I can still view videos related to cryptos and trading so they are not entirely screening crypto contents maybe some particular influencers who go against their community terms.
Maybe it's not a policy change from YouTube, but there are some reports that YouTube might receive from people watching videos about Crypto.
People can report any video and be reviewed by YouTube. Maybe the report deleted the video on that channel. but for other channels that contain crypto is still safe and can be watched.
I also think the same, because no TOS has changed, only stronger toward sentiment towards massive reporting actions, YouTube removes video content that leads to bitcoin buying suggestions, or suggestions and guidelines for other crypto investments.
YouTube is still in a position to prevent, but it doesn't make sense to consider that the deleted content is considered to be in the harmful category, they need further research on this.