Interesting history of your self-execution theory:
“Jefferson Davis contended in 1868 that Section Three was self-executing and barred his treason prosecution, and Chief Justice Salmon P. Chase agreed with those arguments as a circuit judge presiding over the proceedings in Virginia.[8] But shortly thereafter, the Chief Justice issued the first opinion on Section Three and held that the text was not self-executing in Virginia and—in the absence of congressional action—did not apply to a Black criminal defendant there.[9] Following these inconsistent rulings, Congress enacted a Section Three enforcement statute and federal prosecutors brought many actions to oust ineligible officials, including half of the Tennessee Supreme Court.”
https://constitutionalcommentary.lib.umn.edu/article/amnesty-and-section-three-of-the-fourteenth-amendment/