Anyone tried to hijack big community sections?

Seems a lot of community sections only require you to be subbed to the channel for one day or seven.

Has anyone tried to post links there?

I tried it in a smallish group and my YouTube link went through so maybe you could join and funnel people to your video and have a pinned comment with your funnel link or affiliate link?

Never tried a direct link to my site tho so could be an interesting.