@kelvin0mql In cases where I give the cards out, it's mostly to avoid being call Ms/Mr Castellucci or being called sir/ma'am in situations where I expect to have repeated interactions with people like flight attendants and waitstaff. My stated preference is for people to just call me "Ryan", but I've got my title ("Mx", with pronunciation) on there anyway.
They've also helped with "you don't look like a 'Ryan'" situations, like the time a flight attendant was questioning my presence in a first class seat. It's a unisex name in the US, but not so much elsewhere.