It took you 8 hours to transfer to an external drive.. Hmmmm
Sorry but that's about 5 hours longer than it took me to
Migrate from my old a MacBook Pro to the new one. Not sure
Why it took so long for you.

I cloned the old MacBook Pro info to an external drive first
Before migration. Then did the Mac to Mac migration.

__________________
"What you hear in a great jazz band is the sound of democracy. “The jazz band works best when participation is shaped by intelligent communication.”
Harmony happens whenever different parts get to form a whole by means of congruity, concord, symetry, consistency, conformity, correspondence, agreement, accord, unity, consonance…….