No, the preamble cannot make laws inactive. If you wanted the legislation to have a limited term (like a sunset clause) or only apply in certain circumstances, you would have to put that in the actual body of the legislation. Legislation can only be changed by act of the legislative assembly, even if it has become archaic or obsolete. I think the judiciary can strike down entire acts if the assembly refuses to fix constitutional issues, not sure how that works.
If you say that we have law X because of reasons Y, then doesn’t it invalidate X when Y no longer holds?
No, the preamble cannot make laws inactive. If you wanted the legislation to have a limited term (like a sunset clause) or only apply in certain circumstances, you would have to put that in the actual body of the legislation. Legislation can only be changed by act of the legislative assembly, even if it has become archaic or obsolete. I think the judiciary can strike down entire acts if the assembly refuses to fix constitutional issues, not sure how that works.