Here are some facts:
Zinchencko gave up fewer chances a game that Kyle Walker. Was caught in possession fewer times
Add to that, he had more key passes, created more chances, more assists , and we also won every game Zin started on the left.
According to the numbers we are weaker both defensively and offensively at Rightback. For good measure, Zinchencko leads the team in tackles per game. 2nd in interceptions. Ota has a better average. Then again Ota' played so few games that his numbers are skewed. So really Zinchencko was the consistent starter who led the team in both interceptions and tackles. Has a 91% pass completion rate. In case you thought he gave up the ball too much. He doesn't. That too is better than Walker's or Danny Lowe's. Touches per game? 84, 2nd only to Larporte at 85, no one else cracks 74 touches.
These are just some of the facts that gives me pause when this discussion comes up. It's as if the facts don't matter.
Can we get better at Leftback? Sure. Do we have a weakness at Leftback? No we don't. Not even close.