Wow the ... animosity sometimes can be interesting. Nonetheless to answer your question, from many folks I've talked to over the decades.. preop, post op, non-op, blah blah.. from all I've seen its a bit of a russian roulette crap shoot. Some folks can, some folks can't... some folks lose the ability to have any sexual feelings, others don't. There is no one definitive answer...unless you have a orchi or srs THEN you will most certainly not be able to produce sperm (of course).
That being said I'm a girl downstairs, no testes, but I fully produce plenty of secretions... and frankly some of it still at least looks suspicious to me at least. Oddly the higher my estrogen levels, the more I can produce. Has nothing to do with testosterone as I generally have none (or non measurable amounts).
If you really really must have sperm, and you notice things diminishing I'd stop HRT right now.. the damage is generally reversible. Again though, not always! Sometimes permanent damage is done to the testes on HRT. You should have a serious discussion with your medical professional that is prescribing these medications, and review your options. There are many I hear that opt for sperm banking.
