The ERA Solidifies Women's Rights in the Constitution as the 28th Amendment

[SickOfTheOnePct]

19. Yes I've read the Tribe article

At the bottom of the case summary below is the opinion from SCOTUS on that case:

The Court has generally followed the Coleman [ v. Miller (1939)] approach whenever it has been asked to interpret the Constitution's Article V, leaving questions regarding the article's interpretation to Congress. Consider NOW v. Idaho(1982) in which the issue was a 1978 act of Congress that extended the original deadline for state ratification of the Equal Rights Amendment from 1979 to 1982. The act also rejected a clause that would have permitted state legislatures to rescind their prior approval. In the wake of a strong anti-ERA movement, the state of Idaho, which had passed the amendment in the early 1970s, decided to ignore federal law and retract its original vote. The National Organization for Women (NOW) challenged the state's action, and in 1982 the Court docketed the case for argument. But, upon the request of the United States, it dismissed the suit as moot: the congressionally extended time period for ratification had run out, and the controversy was no longer viable.

OPINION:

Upon consideration of the memorandum for the Administrator of General Services suggesting mootness, filed July 9, 1982, and the responses thereto, the judgment of the United States District Court for the District of Idaho is vacated and the cases are remanded to that court with instructions to dismiss the complaints as moot.

https://edge.sagepub.com/epsteinshort9e/student-resources/chapter-1-the-living-constitution/now-v-idaho-1982

If SCOTUS rejected the validity of the deadline, why did they dismiss the case once the deadline had passed?