How can I create a simulator for an iPhone 6 (runninf iOS12.4) in Xcode 12.3? Entries in the Simulators list shown in Preferences->Components are all greyed out. The entries go up to iOS14.2. If I try to create a new Simulator by clicking + in Window->Devices and Simulators, Simulators tab, the only OS version available in the dropdown is iOS 14.3. If I try to download more Simulator runtimes I see the greyed out list shown in Preferences->Components.
You can install additional Simulator runtimes in Xcode Preferences, or on the command line, by following this useful guide:
https://developer.apple.com/documentation/xcode/installing-additional-simulator-runtimes
I cannot install from XCode Preferences as all the simulators listed are greyed out. Will command line installation be any different?
Even though the options are greyed out, clicking on the download (down arrow) icon shows a screen "Xcode is trying to install Apple-provided software" and prompts of credentials to allow this. The simulator download then proceeds and the greyed out down arrow is eventually replaced by a blue tick, and simulators for devices using the downlooed iOS appear in options.
This is typical Apple. Iphone 6 with iOS 12 is nowadays still supported by Apple (only iPhone 5* does not have support) but you do not have any way how to test it! Simulators support only newer devices! Thank you great Apple!