Hello, Chris!
I fully appreciate your concern. Let me explain the situation that I and others may be in. For whatever reasons, my faithful client, a long-time Apple fan, has never been able to quite keep up with Apple, and is unfortunately still shipping a large scientific application based on Metrowerks Power Plant. When this client asks me to fix something, I can either hack the current version of Xcode as described in this thread, or install and use Xcode 3. If I choose the latter, I must suffer through
• Waiting 8 minutes for a simple ⌘⇧F *Find Text in Project*
• Breakpoints that usually don't work in C++
• Using Terminal.app for all git operations
• Worst of all: Remembering how to use Xcode 3
To your point: Yes, when we build this product with the 10.6 SDK in the Xcode 6-8, it will crash inexplicably when performing certain operations. So for some debugging tasks, unfortunately I need to push changes, then use xcodebuild on an old Mac which is running Xcode 3. And, of course, I do this for release builds.
But the ability to edit, and usually build and debug this old project in Xcode 8.1 makes life livable. I hope that Apple appreciates this and would never do anything on purpose to make this any more difficult 🙂