Yes you can download apps outside the App Store, but the App Store has a brand recognition associated to it that Apple need to and should protect.
If anything hurts their brand its the utter lack of carring for the osx platform.
The app store has nothing to do with that as most normal users dont download anything.
The mac was considered secure long before the app store.
This is short sided. $AAPL cash cow is obviously mobile, however I don't agree that they don't care about desktop. I assume your referring to the blog outrage about the new MacBook Pros? News flash, the bloggers who were complaining the loudest and making the biggest noise on HN and in the news are a small minority. Notice how you don't see daily stories bashing Apple as much now.
See $AAPL chart: https://www.google.com/finance?chdnp=0&chdd=1&chds=1&chdv=0&...
Today's OS X development is pretty lame by those standards.
- Introduction of an OS-level hypervisor (Hypervisor.framework).
- Much better security and resistance against rootkits (SIP).
- A new filesystem (APFS).
- The introduction of a far more modern programming language for development (Swift).
- A new graphics API (Metal).
Sure, some coincide with features added to iOS, but I see that as a strength. There are also user-visible changes, but I care less about them. To me, the WIMP paradigm seems to have reached a local optimum and I don't think anyone is helped by Windows 8 or GNOME 3.0-like experiments.
OSX releases before Lion had much more innovative stuff, e.g.
* 10.4: spotlight, dashboard, automator, CoreImage, CoreAudio
* 10.5: time machine, spaces, cover flow, quick look, boot camp
Those are user-level improvements.
- Dashboard: never used it. Fiddled for 10 minutes and decided it's not useful.
- Automator: maybe some Alfred workflows that I use, use automator, but I never used it directly. I also don't think anyone outside power users write automator scripts. And these are the same people that can benefit from APFS or Hypervisor.framework.
- Spaces: gone. I am still sour about this though ;).
- Time machine: not that great in practice. Especially with a Time Capsule/Airport often results in backup sets that are broken.
- Cover flow: never used it, not saw the point.
- Boot camp. Never used it.
So, I and most Mac users that I know don't use half of these features. I also know quite many non-techie users that don't even know that Spotlight exists (they launch applications via the Dock and use Finder).
Also many people who use the mac are people who use it to develop other things like web services and ios apps. They use it as an actual actual productivity platform and create much of the value of the iPhone ecosystem.
Apple is basically lining up for it's own demise in the long run, the more they tighten the rope around the developers and kill much any of the thinking which should be helping them build the fundation of the future.
But perhaps the mac have just become a nuisance which needs to die. In that case they are doing a great job.
The stuff you list is nice if you're developing software for the Mac, I suppose. I can't get too excited about the prospect of better software when the underlying OS is getting steadily worse.