Every trailer has heavy editing in terms of Sony Vegas/ Adobe or whatever program they are using. It can take a lot of iterating to get just the right times on sound to video but that doesn't mean the video quality is necessarily changed because of it.
To give an example, some time ago I made a fan trailer for TW3. It took me about 2 dozen hours to do it and it involved heavy editing.
https://www.youtube.com/watch?v=V6fPvt4jfFs
Then there this older one I made for ME3. Tons of editing there as well:
https://www.youtube.com/watch?v=U69RITfKPOg
Sword of Destiny being referred to as CGI still doesn't account for the gameplay reveal trailer in 2013 or the VGX trailer nor does it account for CDPR statements that the game would significantly better looking then SoD/VGX.