Google is being spammed by video content more nowadays. Spammers are finding top-ranking content and with the use of text to speech tools create a video of the same content. After then they use the same background image in the video and rank their video.
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Roger Montti posted this on twitter and according to him, spammers are using more this technique to spam Google.
Tweet By Roger Montti
New form of spam. Scrapers use Text to Speech software on your content then copy your featured image for a video, then upload it to YouTube to spam Google Organic with their auto-generated videos that rank for your topic. @JohnMu @dannysullivan
— Roger Montti (@martinibuster) December 27, 2019
According to Roger Montti, this technique is showing great results on Youtube over various political topics. But as for now, those videos are showing up in organic results.