Yeah true but in eternal league, the damage from reflect isn't enough to really make a difference , even with so much reflect % damage and lots of general damage as people already have such large damage Reduction in arena anyways and lots of HP. If not, more damage Reduction than HP with Regen to the point where reflect is nothing.
I do remember one time when reflect could be potent with the explosive affix and other combos but CV is better off than reflect. Even back in 2.0 when arena was first around , reflect was hardly useful but there were a few odd build that power a challenge with the reflect .
Mana shield build though counts as reflect in some form but once their shield is down, they are vulnerable to death due to low HP or so.
CV acts like reflect and is actually deadly . Shieldwall has reflect but the reflect doesn't do much damage generally .
The only time I found reflect deadly was when I had sanctuary facing the immortal build and the Shieldwall was enough to kill me which meant I had to time my attacks carefully without death, after enough draws. I know with my experience with facing @Mr_Scooty for the first time when he used the Shieldwall with immortal build.