Inclusivity — To add your pronouns, visit your profile, then tap “Edit Profile” and you should see a pronouns field. You might need to update your app if you don’t see it yet.
It looks like Instagram is only allowing some of the more commonplace pronouns at launch, but it also has a help form on its support site where you can submit requests for pronouns that aren’t available as options. Instagram says it will update the list over time.
Adding pronoun options is a simple change for Instagram to make, but one that can help users who don’t want to exhaust themselves repeatedly informing others how they should be referred to and maybe feeling like they’re not being seen as they are.
Hopefully other platforms like Twitter will follow suit.