it was explained somewhere (OP?), Chinese community i think it was?, brought to light to toxic gang the benefits of crit dmg and crit scaling because they were stacking crazy OA already, this lead to new crit meta in general, specially for skills/builds with attacks that had innate crit scaling (like AAR etc).
Lee also already had a concept build prior, showcasing that high OA was also a benefit in ex Ravager clear, because going from, numbers pulled from butt, 80% hit chance vs 100%(3k vs 3500oa), meant both better lifesteal and dps thus better clear. *obviously not universal and iirc he also wanted to show another point in terms of squish pre 1.2? or something/swiss cheese memory
High OA just beneficial in endgame when both SR and Celestial DA/debuffs are invovled (and crit multiplies dmg by x each new PTH rank 🧮 Critical Hit / Resistance Calculators - DPS multipliers)