"Meh, just AR, not true holographics" was such a classic shallow dismissal that it should be easy to understand why so many readers, including me, reacted negatively.
No one is calling every critical response dismissive nor compelling anyone to use gentrified business speak, false pleasantry, or any of the other things you're worried about.
Edit: one thing that you and the GP appear to have in common is a pre-existing understanding of "AR as an inadequate stopgap on the way to holography". Ok, that's interesting! but the context that pre-exists inside your (or anyone's) head doesn't communicate itself to others. It needs to be explained explicitly. That can be done without putting down the work of someone else who happens to be working on (say) AR.
If you express the point only as a putdown, without the surrounding information that would make it meaningful, then you're going to feel like you made a substantive comment (because for you it's resting on a substantive foundation that you're taking for granted) but it's going to land with readers (who don't have that internal context) as a shallow dismissal.
By "you" I don't mean you personally, but all of us—we all take our own internal state for granted. For HN to function well, though, commenters (all of us) need to work on not doing that, but rather explaining enough relevant background to make our messages interesting instead of empty or mean. The GP's second paragraph did a great job of that—just not the first bit.