Isn't it a fairly widely known fact that Williams produces all of his own soundtrack albums and has final say on the music? So why is Christian implying that some unknown force or person is responsible for the album presentation? Williams presents the tracks the way he chooses, so if there are micro-edits in the OST tracks it's because he requested them, probably for a more fluid listening experience. It's known how unenthusiastic he is about releasing complete scores for his films for this reason.
You can clearly hear in the FYC why he may have chosen to do so; often the pieces that are edited out are very obvious pick up cues/inserts that work fine in the movie but don't necessarily flow with the music around them.
"[The] music editor" who "squeezed" Holdo's theme into the end credits was not some random album engineer, it was John Williams.