No, you are creating a false dichotomy based on a false premise. It is necessary to the extend that it explains a reason for the 2nd amendment but you falsely conclude that since it is listed that it must be the only reason for the 2nd amendment. It is not the case that it is either their as the only justification or that it is necessary, therein lies your false dichotomy. 

Did you read the article about the wording at all? 

If you don't like the 2nd amendment then try to get it changed, be my guest, use the legal process to amend the constitution. But don't try to twist the wording to try to circumvent the constitution.