We rightly expect more integrity and imitable behavior of church pastors and deacons today than was expected of prophets 3500 years ago.
We rightly expect better theology of our teachers today than we do the Early Church Fathers.
That said, if you claim to be a prophet or a teacher today, you are expected to not model the bad behavior of ancient prophets, or the fumbling theology of Early Church Fathers. We stand on the shoulders of those who went before us. We join in the life of a body that the Holy Spirit has been maturing for thousands of years.
“Not many of you should become teachers, my brothers, for you know that we who teach will be judged with greater strictness.” (James 3:1)
We ought not hold Joseph Smith to a 21st century standard, but to a reasonable 19th century Christian standard. By giving Joseph Smith a free pass to secretly marry and sleep with teenagers behind Emma’s back, Mormons have rejected the millennia-long maturing work of the Holy Spirit on the body of Christ.