I think the feeling of intrusiveness is the same for both devices but the difference is the ease of confrontation. Its much easier to confront someone with a camera because the intention to shoot a photo or to capture a moment is so clear and honest. Whereas someone with a phone can minimize the intent by saying they're only snapping a quick insignificant photo for any millions of reasons and we have to accept that or look unreasonable.

I think this is the part which gets closest to trying to explain any of the "why". To me, the largest portion seems to come down to most everyone having used a phone for personal photos in the last 20 years and very few have ever used a phone for professional photos (partly because most are not professionals, partly because if they were they tend to like "real" cameras). Framed from the perspective of professional cameras, most people stopped using cameras for personal photos unless they happen to be professionals or enthusiasts.

This creates a very strong association with "phone = personal/throwaway photo, camera = formal photo for wide consumption". Naturally, this is not universally always true. One can be using a professional camera for personal photos of their girlfriend and one can take a selfie at starbucks and have a million social media readers see it. While not universally true, I bet even the author would overwhelmingly make the same assumption if asked to bet money on the intent of random photographer setups while walking through town. People are just making the same assumption when they see him at Starbucks with a professional camera.

I too remember the "no photos" rules - in the pre-smartphone era. Technically you weren't even supposed to bring a camera in to the workplace (though this was mostly unenforced).

Now you can take pictures and videos of everything, willy nilly, and nobody bats an eyelash. With a camera that you always have with you, whether you anticipated taking photos that day or not.

And yeah, you can't play shallow focus games (notwithstanding that the phone will fake shallow focus with algorithm). And you don't get real zoom (pinch zoom doesn't count).

Oh, on the "real camera" front. Show up with a Canon SX30 ("big" camera, lots of glass in front) and people might notice. But show up with an SX210 (these are cameras I happen to have) and you can get great stealth shots with its 14x zoom but no one the wiser. It's just a small point and shoot, harmless, right? This thing is leaps and bounds more capable than a camera that size back in the pre-digital days.

I'll bet a Gopro will get a pass too.

We were just taking fashion photos on the street in front of our building, turns our neighbours across the street at the MI5 were not super excited about this though.

> Both devices capture identical images.

This is so obviously false. The photos definitely don't look identical. If you're carrying a DSLR, it's a darn good bet you believe it'd take better photos than your phone. And someone who does so is going through the trouble of carrying one is more likely to spread the photo publicly than someone who's using their phone. Hence the stronger reaction.

It's always sad to see when people tarnish a good point with bad arguments. Doubly so when you're accusing other people of acting irrationally, based on clearly false premises. It hurts the cause you're trying to advance rather than helping it.