The saints weren't perfect. If your main complaint is that he likes someone who isn't perfect he sounds like a pretty decent priest to me. Jordan Peterson was a stepping stone for a lot of people, including me. Yes he has problems, but I think Fr Josiah primarily sees the good in him especially when contrasted with our world today.
I have a different hypothesis here: I think Fr Josiah is secretly trying to convert Peterson in spite of his own heretical beliefs. Saving the heretic, especially someone you know whom is actually a good man and is good to his Neighbors, is something Jesus would want us to try and do. Jesus befriended all kinds of sinners and saved many who repented. Likewise this point is repeated within the Parable of the Good Samaritan, the Samaritan gets involved with someone else's personal lives in order to help and save them, despite being different from them in nearly every way.
Rather than having immediate suspicion of a religious figure, reserve judgement and see if perhaps there is something more to learn? I am almost always surprised at the reasoning of devout Orthodox priests on tons of issues, which is why it is a pleasure to speak with most of them.
My priest befriended a homeless drunk. He let him attend services even though he would stumble in reeking of alcohol and slurring his speech. In spite of how much of a terrible wreck this drunkard was, he professed his faith in God and Christ and begged for mercy every time he showed up in Church (which was more often than most Orthodox I know). My priest gave him shelter and food as much as he could provide, and the drunkard saught forgiveness for his sins (even though he could not recover, he was too far gone and died an alcoholic). Whether or not the man was truly saved or not is irrelevant. We only need to do what God called upon us to do, which was to heal the sick and provide nourishment for all of the sick and destroyed souls out there. God will handle the rest and judge infinitely better than any of us could, so it is not up for us to judge others for their personal sins - even if they are heretics!
When it comes to matters of the spirit, remember the first rule, "nothing makes sense." God being infinite means there are infinite ways for people to experience conversion. Reading lives of saints reveals that no two saints have the same conversion process and it almost never makes any sense how it happens, such is the great power of God.
Fr. Josiah Having a picture with someone who is influential among conservative youth is just a good way to build a friendship and perhaps plant the seeds of conversion in Peterson's mind, and in Peterson's followers. There is no harm in trying, yet incredible gains if Peterson does find it in himself to seek God. Not to mention as well, the hundreds of stories of men who end up reading Peterson and somehow finding God anyways show that perhaps his picture helped saved many. It's impossible to know for us, but we need not worry. Our only duty is to try.
I found this interview by Father Josiah very interesting. Father Josiah is interviewing a same-sex attracted (SSA) professor of Biblical studies on his book on his struggles with chastity and life in Christ:
Dr. Hill makes the point that we're essentially calling gay people to something like asceticism without either the support system that monks have in their monastery, or that married couples have through each other. Additionally, churches usually offer significant support to heterosexual couples in the form of premarital training/counseling, but they don't have good answers to SSA individuals. Also, married couples in churches have a mutual fraternity with other married couples which allows them to reinforce living within the faith, but for SSA individuals often excluded from such fraternity/family life, the struggle is much harder.
Dr. Hill is Anglican, but in his research he appears to be digging into the Church Fathers and older Christian ideas of friendship in order to think about what sort of support mechanisms could be created to help SSA individuals maintain chaste lives.
Another solution, that worked for probably thousands of years, is for gay men to simply marry a woman they won't have sex with. This is actually easier than it sounds, since gay men often have girlfriends who are ugly or insufferable, and would make good marriage candidates for. They could simply have a platonic marriage where they keep each other free from sin.
A much bigger problem the gay man faces is the same one all straight men face, which is a serious lack of marriageable women.