Presbyterians can be Christians, but the teaching they hand out can prevent them from ever being saved. There is only one way to be saved, & its not by church membership nor by being baptized.
A good little book to read is,"The Little Baptist."
It might be humbling to remember, God's way is the only right way, & mans way will lead people to the pits of Hell.
Mt 15:9 But in vain they do worship me, teaching for doctrines the commandments of men.
Mr 7:7 Howbeit in vain do they worship me, teaching for doctrines the commandments of men.
There's many that does this, including the Presbyterians .
And of course.
Joh 14:21 He that hath my commandments, and keepeth them, he it is that loveth me: and he that loveth me shall be loved of my Father, and I will love him, and will manifest myself to him.
At the same time however, a lot of churches can do that. In my family we were raised IFB, and what we were taught about conversion most of the time was wrong. One of my brothers was a false convert for years, baptized and everything, until he came to me about it, and we went through the Scriptures for the better part of an hour, and prayed, God saved him. Every denomination has their doctrinal mix-ups. Presbyterians (at least the orthodox ones, there are some crazies in there, but there are crazies in IFB as well, to be fair.) do hold an orthodox position of the requirements of salvation, being faith and repentance toward God. The Westminster Confession and Catechism teach it at least.
I was just using Presbyterian as an example, for I know some very Godly Presbyterians. There are also Methodists (we sing a lot of their hymns, after all, don't want to leave them out.) Episcopalians and many people in other denominations that do hold to the essentials of the faith, and that is salvation by grace alone, through faith alone in Christ alone, though they differ on the grounds of paedobaptism. Are there extremists? Yes. Are there false teachers? Yes. But they are in ever denomination.
It just seems there was a bit of elitism in some of the statements, so I just wanted to provide some food for though.