I mean, you obviously feel you were reasonable and are comfortable with your behaviour and reaction, so I am genuinely confused with you asking here, given you've stated it won't impact you any way? Why are you giving it headspace when you're never going to speak to him again, and you're not interested? Your behaviour, as much as his, is done now, and you've blocked him..
That said, you did ask, so. I think you were well OTT and to be honest, rude. I understand you found his question rude (and I can totally understand why - if you're dating with a view to relationships, sex coming up in the first hour would be off-putting IMO, I fully agree), but you don't always need to respond to a faux pas with rudeness.
A simple 'I don't feel comfortable with that question, and it tells me we're incompatible, so I'm just gonna head home' or something akin, would have sufficed. The immediately getting up, grabbing your stuff & leaving without a word, regardless of how calmly you think you executed it, was done for dramatic impact. I'm reading this imagining witnessing it, and I honestly cringed, more so at your reaction than to his question to be honest.
As a woman, I really couldn't be arsed dealing with a woman who chooses to communicate this way, and I'd feel like I'd dodged a bullet. Never encountered someone in real life that huffs like that (who isn't around age 8).
Not acting like a petulant child in response to something you heard that you didn't like, doesn't equal lowering your standards to accept behaviour you don't like, nor siting through a date out of politeness. There is middle ground whilst still holding your boundaries strongly.
I don't think he should have asked. I can see why he did. Some people are open and will talk about anything (my kind of people), some don't. You don't know this really until you get talking to someone.
It appears, in my opinion, you've a strong desire to come across as super high standards and not tolerating anything you don't like. Sadly I think the impact you actually had was flouncy, hard work and infantile. I don't think you came across well either. Incompatible, both dodged a bullet.