Nor should it be. For Tomlinson or any coach. It’s a slap in the face to every player on the team. “Well, boys. We have a delicate waif of a rookie at QB, so we are gonna just focus on his development and not worry about the wins this year.” How does anyone think that sits with the veterans on that team like Hayward, Fitzpatrick, Watt, etc. who know the deal better than anyone?
You play the guy who you think gives you the best chance of winning. Full stop. And if Pickett has to take his lumps early on, he just might be better off for it in the long run. But you have to find out, regardless. The important thing for a coach is to support him when he struggles and help him to develop his game in spite of those struggles.