...but if they've been with the service, let's say Netflix - as you eluded to, since it's inception, then I would think that they would know the answer far better than an engineer that's only been around a month or so.
What you're taking for arrogance might be the engineer simply stating that they've been around the block or two and, having had people try to discredit them before, they want to establish that their experience trumps someone else's own arrogance.
It's not the best way to put it, to be sure, but people have different ways of expressing themselves and/or different expectations of others.
The problem is two-fold: Understanding everyone's personalities and their expectations; and then using that knowledge to build channels of communications with those principles in mind.
If you haven't heard of Insights trainings[0], I highly suggest checking it out.
Anyways, so while one engineer might care about other things, which I might find arbitrary because I only care about the datasets (e.g.: something tangible), it doesn't mean that either of us are "wrong". Just because all I care about is the data surrounding a bug defect doesn't mean I'm an asshole, compared to someone who cares about the end-uer's experience. We're simply driven by different aspirations.
The same goes for your jerk engineer. Maybe they're tired of people trying to disprove their statements and tack on the, "I'm that good" at the end precisely because they're tired of the bullshit, A-type personality shit that comes with everyone trying to one-up them to look cool. Or maybe they're actually a jerk. I don't even pretend to claim to know.
...but immediately attributing malice, where other answers can just as easily suffice, does everyone a disservice because you don't rely on communication to understand the why behind whatever was said. You take this assumption you've made, let it create a bias, and then that bias affects your interactions with them.
All of that could've easily been avoided by a simple, "Hey, man (or chica or your flavour of vernacular), I wanted to ask what's up and see if you knew/understood/comprehend/what-have-you how what you said came across when...." A lot of the times, you'll probably find that they had no intention of it sounding like that but 'x' was on their mind or some other factor was in play. You could also find out that they are, indeed, a jerk; but that would, at the very least, be a confirmation and not just an assumption, yeah?
Anyways, this was a long, fuck-all, pointless diatribe to say that someone might come across to you as a feckwad but it doesn't - implicitly - mean that that's who they are, in their day-to-day.
I've experienced people I thought were arrogant as feckall, until I had 1:1's with them and got to know their personalities and perspective a lot better. Once I understood where they were coming from and how they think and/or react to things, I could tailor my behaviour better towards their personalities and they could do the same in kind.
(Sorry for the feck-all novel.)
In both cases what the person is suggesting is in fact the right way to go most of the time. The difference is whether or not you feel you're better than everyone else.