jackchong890, no problem with the paint by itself. Many development is using this paint.
It is a finishing paint, not a base paint.
If your contractor use the paint as per manufacture's instruction, it will not give you any problem.
Your contractor is highlighting your colour selection, not the selection of type of paint.
What he try to tell you is not many people want to use pure white on wall due to maintenance issues.

With a coat of sealer and you use them as per manufacturer instruction. You will not get this problem.