I'm not saying many clubs do it the exact way Arsenal do, every team does it in their own way. Zinchenko is obviously a different player type to White/Tomiyasu and very comfortable on the ball so we build down his side more often.By the sounds of it you must watch more than me! I know a lot of teams now line up with 4 at the back but build with 3, although how many teams do it in such a defined way as Arsenal?
Chelsea tried it with RLC coming in from right back but it looked a mess. Liverpool have started inverting Trent more but that’s more to get him into half space crossing positions in the final third as opposed to actually building the play like Zinchenko does.
I’ve only really seen City do it to the extent we do it in build up (I don’t watch Barca or Bayern). Saliba will be on the ball and Zinchenko will be moving into CM to pick it up off him, it really isn’t that common from what I’ve seen.
Which at that point you have to ask yourself what player around can do that role better than Zinchenko? Not many for me. So in my opinion it yes it was a specific style of player Arteta wanted (Martinez would have done this role as well).
When Bayern play Davies they use his pace and propensity to move into the attacking third to build lopsidedly from that side with Kimmich dropping deeper there, when Lucas is at LB and Mazraoui plays on the other side they do it on the opposite side with Goretzka closing that space.
I think what TAA does for Liverpool is exactly the same as Zinchenko doing here. You're making it sound like he's some crossing merchant or that "actually building play" can't be a long ball like Zinchenko has never done it. TAA is hopelessly atrocious defensively, the only reason they've been getting away with it is because of his qualities on the ball.
Every coach looks at the players they have and tries to emphasise the strengths of his players while masking their weaknesses there's nothing special about it. Martinez would've played a vastly different role imo, he's good on the ball but a CB by nature not a CM.