In theory, theory and practice are the same. In practice, they are not.
The Russian analyst in that video presents theories to doubt Javelin effectiveness, but in practice, they blow up Russian tanks real good.
He’s Serbian, not Russian. He’s been ‘around’ for about a decade.
You might also want to look at his other videos - this sort of analysis is common among the popular and growing milsim community online:
https://www.youtube.com/watch?v=W9_OYdfF-EI
https://www.youtube.com/watch?v=Kn4elQ1WknM
https://www.youtube.com/watch?v=Kn4elQ1WknM
https://www.youtube.com/watch?v=f6iIMfNRVZo
https://www.youtube.com/watch?v=2gtU54NVZ-k
The milsim software is also why you shouldn’t believe everything either side is putting out:
https://www.youtube.com/watch?v=It-Ad7bCE50
https://www.youtube.com/watch?v=Xjka0IYe4lo