>>If I see someone whose theology is so flawed it impedes their salvation, do I not have an obligation to tell them the truth? <<
If you explain your posititon on why you think you are right, you have done your job.
Remember, that is only your opinion. Mine is different. In my mind YOUR postition is wrong. Just because I state my position on a forum doesn’t mean I want to debate you, it means that I am stating my position. When you continue to tell me how wrong I am, you are overstepping what you need to do. As a Christian, you have spread the Gospel. You think your position is right, I think mine is.
Let the Lord sort it out.
Well, the Lord WILL sort it out eventually (and fwiw I think we probably are all wrong about some thing or other).
But, if one puts their position on a forum, they should expect debate, whether they want it or not. I don’t really like debating religion myself, so I rarely stake out an opinion (I don’t think this is the place to spread the Gospel, not because I think it’s inherently wrong, only that I don’t think I do a good job of it).