> But when the sun does look yellow, its light is yellow too, that’s the definition of "looks yellow".

Not quite; the sun is far away and is restricted to a tiny portion of the sky, but its light covers half the earth at a time. It is simultaneously true that the sun looks yellow and that the light we receive from it is white. It isn't the case that objects in direct sunlight are yellowed by that light; the yellow appearance when you look at the sun is something of an illusion.

> Even though a lot of the blues are scattered around, the sun still looks just white when it’s high in the sky.

This isn't true.