Yes, it was a mistake.

The 26th Amendment lowered the voting age to 18 for all elections.

Glenn Reynolds, deploring the politics of notoriously intolerant left wing Yalies, says the amendment was a mistake

The text.

Section 1. The right of citizens of the United States, who are eighteen years of age or older, to vote shall not be denied or abridged by the United States or by any State on account of age.

Section 2. The Congress shall have the power to enforce this article by appropriate legislation

The recent rise in aggressive feminist misandry and Hillary's use of what is becoming a routine campaign theme of casual man-hating suggests the 19th Amendment was also an error.

The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of sex.

Congress shall have power to enforce this article by appropriate legislation.

That and the fact that in their own eyes the most important thing women have done with the vote is give themselves the right to murder their babies.