The channel was active with videos uploaded consistently that were getting millions of views but its last videos didn't get as many views as before so the owner allowed me to try CPA videos on yt so we could split the profit.
I uploaded my video with good SEO optimization, good thumbnail etc. Applied my methods to rank (buying views, likes, real comments and other twists that I won't reveal) and it still didn't rank.
Now you will probably wonder why I didn't "warm up" the channel or something. Well, I never do that with my other channels and I'm still able to rank. I've been able to rank and revive channels that got like 10 views a day from the old videos without warming them up, so channel preparation is not really required in CPA.
What I've learned from this? That at some point YT algo punishes certain channels, rendering them useless in getting organic traffic. But I've also came across this kind of shadowbans on channels that haven't had videos uploaded them for 10 years. Trust me man, hundreds of not thousands of channels came through my hands in all these years so I know for sure that some channels rank and some don't. I know high earners from OGAds that also earn like 1k/day on YT and they came to the same conclusion.