I disagree. There are some points in eloquence that can be seen to be eloquent objectively. The degree of amazement and wow factor will differ person to person, but you can point to amazing eloquent signs. And when they add up in Quran, they make a cumulative case.
Some of these signs are best seen in Arabic. Some of the eloquent signs in terms of eloquence don't require that.
Education produces eloquence. By your criteria, an educated person could do no wrong (because they speak eloquently). Therefore, they could murder their wife (while composing eloquent poetry, of course).
Not all educated people are saints. Many Nazis were said to have very high IQs....and saints they aint.