softening, mitigation
雍 centers on making something less severe or harsh: softening a blow, mitigating pain, or easing a tense situation.
雍 is thought to combine 隹 (bird) with a phonetic element, possibly related to harmony or blocking. The exact historical development is uncertain.
The top 亠 looks like a lid, and the lower part suggests a bird (隹) being calmed. Imagine placing a lid over a restless bird to soften its agitation.
For ヨウ, picture a gentle yoga instructor named Yoh soothing a tense bird under a lid: Yoh -> ヨウ, and the bird softens.