Apple seemingly did good with audiobus on iOS7, and coreMIDI, NetworkMIDI and the IAC bus are all attempting at least to help musicians make music on computers. It's better than the competing alternatives. (I can still bring down my system with MIDI feedback though!) I'll give them the benefit of the doubt. AUs seem a bit half baked, considering most of them are wrapped VSTs, but I don't know if that's because of developers fighting it or not.
I hope the companies that make stuff I like and bought products from stay in business, but I'm not going to blame apple if they don't.
I like a lot of plugins, but it's in spite of all their crap, not because of it. Most plugins make waldorf look good in terms of bugs. Is anyone surprised when a plugin crashes any more? It's a like a bad joke about an abusive spouse, "Honey, you know how I get, it's your fault for not saving!".
Compound that with a major selling point of many plugins is their "workflow efficiency" you've kind of lost the plot. Why sell cheap plugins then? The people that care about workflow efficiency can pay thousands of dollars. Gee, I could spend money on an efficient workflow, that probably crashes or get a module/ korg volca to jam out on and save up for an analog mono synth? Ever wonder why most software developers use hardware if they make music!
Everything goes in cycles. I think 3rd party plugins are on a downturn regardless of what apple does. When you've bought Live Suite, Push, (or Logic, Maschine and Komplete) an audio interface and a laptop can you afford anything else? Do you really even need it? Max for Live will supply free content for years. I don't think Native Instruments cares about selling plugins because I'm sure Maschine Mk3 will be capable a host. if it isn't MK4 will be!
Sonar? Haha. Gibson. So Digital Performer, Protools, Fruity, Reason? All pretty great stock plugins. Cubase, for now. Most of the obsessive plugin collectors got into eurorack.
It's like back in the bad old days some dude got rich making a program called winamp to play MP3s.
You'll still be able to sell plugins to engineers and people that mix for a living?