Without knowing the specifications of this design, the moment I see columns numbered numerically, I cringe. Then I cry. This design pattern usually indicates a bad design.

I would posit there is a more optimum way to store the data so that you dont hit the limits, you can access the data without a ton of crazy code and you dont use NVARCHAR(MAX), VARCHAR(MAX) or any of the MAX variants, for obvious reasons.

If the original script was for NVARCHAR(255), why convert to NVARCHAR(MAX)? Is it "just in case"? If so, that is NOT enough reason to use VARCHAR(MAX).