37, trans woman... I haven't had 'the operation', but I experienced something similar to what you describe... Not to the same extent you did, but my libido dropped quite a bit after I started hormones. It's higher now than when it was low, but it didn't climb back up to where I was before I started. I also feel like I dropped at least a full Kinsey point, to use an overgeneralizing metric about sexuality -- I used to be considerably more exclusively woman-attracted, and while I'm still more sapphic than not, I'm definitely not like a strict lesbian anymore ^^

It's... possible that your sexuality has changed in that regard too? Do things feel different for you if you fantasize about different genders/gender expressions?

It may be that a different mix of hormone medication might help the situation. Do you know what your estrogen levels are, and how they compare to what doctors usually expect for post-op trans women on hormone therapy? (I saw your response to another comment that it's hard to get access to knowledgable doctors, but like... if you can at least get labwork done that would be something your other-country doctor might be able to use to give a recommendation!)

Also, not sure if you're on progesterone or not, but I went on that a year or so ago and I feel like that helped noticeably. I took it in two-week-on, two-week-off cycles for a while. When I'm on it, it makes me a more groggy in the morning, but then later in the day -- and especially in bed -- it gives me more energy. (Feels like that, anyway!) Over time my libido came back up whether I was in the "on" part or the "off" part of the cycle. I've also read other redditors say there's an element of like, your body getting used to running on estrogen instead of running on testosterone, so it's possible that the general upswing was because of that, and it wasn't the progesterone. Could have been a bit of both.