I noticed this last night. A live video showing an old Elon Musk + others interview about Crypto currency. The video's live chat was turned off.
The text on screen said if you send them bitcoins they would send you double back immediately, the purpose being to speed up the use of crypto currency.
The video had 12,000 live viewers

, and there were others running that also had thousands of viewers.
Apparently some Youtube accounts, that had a high-number of subscriptions, have been hacked and repurposed to scam people.
Must admit I had to think for a bit - is this real? I imagine loads of people are getting scammed.
It doesn't help that Youtube removed the dislike count, as these were a useful way of spotting fake stuff on Youtube.
This video here explains the scam -