it's more of an improvement than 'of sorts' - Zin is a ticking time bomb so for Arteta to leave him out is really positive, OK Tomi isn't ideal at LB but he's not as much of a disaster area
Disagree. Tomiyasu is better defensively but still too slow to be of any real use, and any (albeit slight) attacking advantage Zinchenko gives us is nullified so it’s kind of like for like in my eyes