That is the conservative or evangelical Christian narrative. However there are many ways of looking at the NT within Christianity including those who are more closely aligned with a Baha'i approach.
I'm just going by what the NT says. I don't necessarily believe it's true or right, but I do agree with the born-again Christians that the NT teaches that sin and death entered the world through one man's disobedience, Adam, and is saved by one man's sacrifice, Jesus.
For all the people that want to soften that and find an alternative interpretation, I don't mind. After all, who wants to believe the whole of the Bible and the NT too literally. But... if it is the Word of God, then it should be. And even Baha'is have called it that. I don't. I think it is made-up religious myth. I don't believe it is literally true, but it might be. And I understand why those born-again Christians insist on taking it literally.
Baha'is seem to be saying is that the "truth" of the Bible and the NT is that it definitely should not be taken literally but to find the "true" allegorical meanings behind the things it says. And those allegorical meanings and interpretations given in the Baha'i writing is presented here as being the real truth. And that's the problem... there is no other "truth". Baha'is seem to be just as stuck on their interpretations of the Bible and NT as any Fundy Christian is for theirs. Which causes nothing but division. With neither side given in, because they both "know" they are right.
Then add the Atheists... All they ask for is tangible proof. Baha'is say that without science, religion can fall into be superstition. Which kind of implies that a true religion should have some objective evidence as being true. But those debates go nowhere. Baha'is say the "evidence" is the messengers, his character, his mission and his writings, or something like that. Atheists says that is not good enough. And Baha'is say that is all they are going to get, take it or leave it. Atheists have left it. Lots of Atheists have been posting anymore in the Baha'i threads. There gone. More division.
Then there is the Hindus and Buddhists... Same thing a unifying connection is not being made. They have their beliefs, and in many ways Baha'is are essentially telling them that those beliefs are wrong. More division.
Can the Baha'i Faith solve this problem? Or is it better to be true to your beliefs that your Baha'i teachings are the truth from God, and they can't be compromised? Yet, it seems as though, the others are expected to compromise theirs. Since, to Baha'is, they are not true... at best, only bits and pieces of their beliefs are true.