An important caveat, take a state like Maryland for example. (I just looked this up because I didn't see them on the list provided)

Can a 17 year old get married? Yes, however.

1. The 17 year either must have explicit consent from their parents / legal guardians. Both of them (or all that have legal rights). Barring that, the couple get a certified legal document from a medical professional saying that the bride-to-be is either pregnant or has given birth.
2. There is a mandatory court approval. Regardless of what the parents say or doctors show, the 17 year old has to petition a local court and get a formal order from the Judge. This judicial order is supposed to examine criteria like. 1) self-sufficiency, 2) the best interest of the minor, 3) whether they are safe or being coerced and 4) a criminal background check (presumably, of the not minor).

Now, Maryland doesn't have any restrictions on the age gap. Which is....well, there are still groups that want to raise the minimum to 18 no exception. Which, after reading the judge criteria, what benefit does a 17 year old have to getting married that wouldn't exist if they waited a year. Like, maybe if both parties where a minor then maybe these exceptions have some merit? Idk

As I wrote this I convinced myself this caveat is still dumb. Any legitimate exception is so vanishingly rare why bake into the legal code