That's a fair conjecture - but even if it were the case, one is more likely to be misgendered than have a pregnancy - so whatever psychological fortification was used for stopping HRT and getting over the shock of the baby bump.... it's not unfeasible this could be done. It might be difficult, sure... but it isn't impossible. The same therapeutic principles apply in both situations.
He could've vetted the midwives - and tbf, that's what I'd advise any trans-man having a baby to do. I think medical staff pre-briefed MIGHT slip up, but I think medical staff who aren't pre-briefed definitely WILL. So there's something in that. You cannot show up as a pregnant man and expect people to have all the correct answers based on your own feelings that they should. That's a very high bar to set.
I said it was 'entitled bullshit' because it is. Because had this particular trans-man been nice, kind, seen how others think and reflected a little bit more - I think he would likely have concluded (as I did) that society was broadly accepting of this novel situation, the hospital accommodated him and staff helped him deliver a healthy baby boy - instead he bitched about their verbal mix-ups in the press. That's what made it entitled bullshit. What was required was a modicum of humility and gratitude. Not just for the staff but for the wider liberal position of Western democracy that has allowed this to flourish. He's managed to take an absolute win and turn it into a complaint.
Consider a similar (though not identical) situation. A woman shows up at a hospital, heavily pregnant. The staff help her deliver the baby... but it turns out she's French. She's very happy that the staff helped her have the baby, but all she does is complain about how nobody spoke to her in French.
That'd also be entitled bullshit.
And yes, your interpretation is correct. If trans-people are accidentally misgendered then that's part of rubbing along together in a shared society, it'll happen - and over time it will happen less and less frequently and become less and less of an issue. If people want to deliberately misgender trans people, then that shows a side of their character I don't really enjoy - but I'm not going to mandate against it. To do so goes against my principles of liberalism and what a liberal society represents.
