It is most definitely not from MSFS 2020, there is not even a 777 available for it.
If its CGI added on top of another video then its extremely well done. Speaking as a 777 pilot of nearly 12 yrs, look at the detail in the wheel wells, undercarriage, flap track fairings etc. Also the wobble in the tailpane, reflections in the fuselage and heat blur and depth of field when passing infront of the KLM 737.
Truly top drawer cgi if it is