[updated October 2024]
From early 2014 through September 2024, I used he/him pronouns exclusively. The first year that I was out as trans, I did, actually, give people the option to call me they/them or ze/zir in addition to he/him, as a courtesy to my friends getting used to the idea of me as not-female. What ended up happening was that literally no one used he/him for me and everyone used the gender-neutral pronouns, which - whether this was true or not - my brain translated this as "people don't see me as male enough to use male pronouns for me" and that's dysphoric ickfeels. Additionally, I've seen some incidents of people gendering others as they/them when they know the person they're referring to exclusively uses he/him or she/her, as a way of subtly and deliberately misgendering the person without outright calling the trans guy "she/her" or the trans gal "he/him" and getting dragged for intentional misgendering. And when I say "I've noticed", I mean that "this has directly happened to me as well as several other trans people I know". [Also, trans people have done this to other trans people, like transmeds who think someone isn't "trying hard enough" to be male or female.]
As of September 2024, I still go by he/him exclusively online, because it's more gender euphoric, but if you're one of the few people who knows me offline, please refer to me as they/them in meatspace unless we're in a situation where it's safe to call me he/him (like in private). I learned the hard way throughout 2024 [at various appointments and during my week-long hospital stay] that using he/him in a red state when I don't pass isn't safe, and she/her is also problematic [I'm not a girl, and I don't look female either], so they/them is the least likely pronoun to cause problems in public spaces.
And yes, as of September 2024 I now identify as non-binary, however I'm still transmasc, I still ID as a guy [I don't call myself a man anymore because I'm not what society expects of men and I'm tired of fighting with people about it, but I'm my own kind of dude], so IMO he/him is still appropriate.