Slack's desktop apps are HTML5 webapps wrapped inside native desktop wrappers. Specifically, Slack uses Github's Electron (formerly, Atom Shell) which is basically Chromium. The desktop app is a webpage inside Chromium.
I guess if that demographic did, there would be less "unix philosophy" cultism, as the efficacy of the unix shell is merely on par with that provided by other relatively coherent software toolsets. The shell is really pretty barebones compared to the rich semantics provided by many toolkits and object systems on which user interfaces have been built: GObject and NeXT are two modern examples.
[That said, where shell shines is by providing so few abstractions that virtually any garbage has the same semantic depth as things which were designed to be used in the shell. Bytes are universal on the common computing substrate.]
The web, on the other hand, is a platform "designed" by the erosive flow of eyeballs during the 1st-nth browser wars, without much of a direction beyond tacking on additional pretty features without breaking backwards compatibility too much.
Attributes like a11y, embeddability, composability, and effective resource sharing tend to simply fall out of well-designed platforms. The web has an effective answer for none of these desirable concerns. Look at how screen readers break on js-heavy and dynamic web pages, the ongoing security disasters of XSS and iframes (and the complexity of login services like Facebook's/oauth/openid), the disappearance of Google reader, and the half-assed way CDNs offer partial, ad-hoc offloading of some resources via surrender to centralization.
...what? The web is better than most native platforms in these.
The web is accessible. It has many features for screen readers and such, but more importantly, it is inherently flexible and allows content's form to be adapted to the reader's needs, thanks to the separation of content from style. A single web page, unmodified, can work on a desktop PC with a mouse and keyboard, a capacitive touch device the size of your palm, a stylus-input device the size of a laptop, a printed page, a screen reader, a ten key mobile phone from yesteryear, and more. The web lets users define custom styling that meets their needs, lets users selectively remove content (ads, for example), etc. No native platform is that flexible. Yes, some sites break screen readers, but this is true of native apps as well.
The web is incredibly embeddable. Any web page can, with one line of code, incorporate any other web page, and it "just works". You simply can't do that with native apps.
The web is composable as well. Sites can load JavaScript from each other very easily.
The web also supports resource sharing in various forms, but people don't necessarily use them.
Indeed, Electron already is starting to provide these kinds of facilities. For example, it allows you to load native node modules, and it provides some tools for integrating with the desktop envirionment (see https://github.com/atom/electron/blob/master/docs/tutorial/d...).
Side note:
> coördinators
I knew I wasn't the only one who loves this pretentious diaresis style. Stay strong, brother/sister/sibling. Stay strong.
"A is not B"
"but A has C properties"
Native apps are not defined in terms of having benefits; they have specific technical characteristics that embedded webpages just don't have. So the fact that embedded webpages may or may not have benefits is irrelevant to the statement that they are just not native apps. I guess that's where downvoters are coming from.
Try hitting Cmd + , to change change some of your HN settings, or alt-tabbing to your HN tab (the one in your browser).
For example, look at Atom. I can type Command-Z on my keyboard to Undo, but it's non-native-feeling in lots of ways:
1. The menu bar doesn't highlight to register that I typed a key equivalent
2. The Undo text doesn't change to e.g. "Undo Typing," telling me what I will Undo
3. The menu item doesn't properly disable when there is nothing to Undo
4. The menu item doesn't respect my settings in Keyboard preferences
etc. etc. And that's just one feature - but it's every feature.
Needless to say, that stuff comes for free or with very low friction natively.
Qt is a bad representative of the native experience, because Qt is non-native everywhere except on Linux, which doesn't have strong UI conventions to begin with. Qt apps definitely feel alien on the Mac.