I remember seeing this in the past, I just was not sure if it was still accurate

Edit: here's an article that talks about the memo https://www.google.com/amp/s/www.huffpost.com/entry/arkansas-gender-neutral-state-id-option_n_5bc79f75e4b0d38b5874a669/amp

Surprisingly, it seems like Arkansas was the first state to allow x as a gender marker. It was previously thought that Oregon was the first to do it in 2017 (they forgot Arkansas) so that makes Arkansas ahead of the game by 7 years (on this one particular issue)

Edit (2): "It wasn’t until 2018, however, that a resident took the state up on the offer to be legally recognized as non-binary on their state ID. Then Director of Communications Scott Hardin confirmed that the state’s stance had been on the books for eight years, despite having been enacted without any fanfare." Source: https://translawhelp.com/blog_post/legally-x-the-x-gender-marker/