Because Russian's war with Ukraine is unsustainable, something has to change for Putin for him to remain in power, and one option is an escalation with NATO. Some other scenarios also explained in this good video https://m.youtube.com/watch?v=jDhYFSGkaAc
Does not pass the smell test. The Youtuber has an axe to grind. Also, tracking in the URL. Why make it more difficult if the current situation is unsustainable? Does not make sense.
It is Anders Puck Nielsen who is a serious military researcher and commentator. He is a go-to by any television channel in Denmark and has been from the start of the war.
He very much passes the smell test :)