That’s not a good contrast. It’s a bad contrast. Discovery and SNW take place in two very different time periods. In SNW, Federation is still strong. When Adira comes out in Discovery it’s during a period where Earth is xenophobic as fuck and the Federation is crippled. It’s a big deal for Adira because they don’t live in the same Universe as the character from SNW. Then there’s the fact that the other non binary character was on screen for a single episode while Adira is a supporting character.

You can’t compare those two so easily while dismissing the surrounding atmosphere.