MacOS – Ports closed on macOS Sierra Can’t Use Apple Services — Terminal Help

First thing I'd try would be a different cable.

Apple has this to say about non-compliant Display Port cabling, though not specifically in response to your particular issue, but Google brought me there whilst on that search...

Certain cables advertised as being VESA 1.1a compliant may contain a construction issue that may result in the DisplayPort power pins at either end of the cable shorting together. VESA 1.1a compliant cables must isolate the DisplayPort power pins at either end of the cable. To learn more about the VESA 1.1a DisplayPort Interoperability Guidelines, visit www.vesa.org

Diagnostic and usage reporting services are controlled in System Preferences → Security & Privacy → Privacy → Diagnostics & Usage. Uncheck both boxes to disable reporting.

You would have been asked to opt-in to reporting when you first set up your computer. You are recommended to use the official switch in System Preferences to disable this reporting. There's a handy switch for you to use, unlike a certain other OS!

If you really want to manually disable the services…

launchctl unload -w /System/Library/LaunchAgents/com.apple.ReportCrash.plist
sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.ReportCrash.Root.plist
sudo launchctl unload -w /System/Library/LaunchDaemons/com.apple.DiagnosticReportClea‌​nUp.plist

With regard to what is reported, full details can be found in that System Preferences pane:

If you opt-in to sending diagnostic and usage information to Apple, it may include the following information:

• Details about app or system crashes, freezes, or kernel panics
• Information about events on your Mac (for example, whether a certain function, such as waking your Mac, was successful or not)
• Usage information (for example, data about how you use Apple and third-party software, hardware, and services)

^{About Diagnostics & Privacy}