>>370077742
It really depends on what your endgoal for the avatar is.
If you want to reduce the poly count, the you can go in blender and decimate the model, but unless the model creator was lazy, the shirts or hats are not very heavy on poly count and the gains will be minimal.
Personally, I don't see any issue with an avatar's poly count as long as it's under 70k to meet the minimum for a "good" rating. "Excellent" rating, while achievable, is not really worth the tradeoff in model detail and functionality.
And even though the avatar rating isn't always a good measure of avatar optimization, it serves as a good starting point and provides a design target for your projects.