Issue fixed in iphonesimulator 23B86 (26.1) installed after Xcode 26.1.1 install and launch. No launchctl unload needed under those conditions.

Was able to xcodebuild -downloadPlatform iOS -buildVersion 23B86 -architectureVariant arm64 during a check twenty minutes ago*. Started an iPad sim and did see (same as these folks) blue wallpaper rather than black, and no MercuryPosterExtension crashes.. This is after 9-ish hours ago, I got iOS 23B86 (arm64Only) is not available for download. output from the same xcodebuild -downloadPlatform command. ⋯ I assume during that 9-ish hours ago period, 23B86 was absent from https://devimages-cdn.apple.com/downloads/xcode/simulators/index2.dvtdownloadableindex but I didn't check at the time. There is a section for com.apple.dmg.iPhoneSimulatorSDK26_1_rru_arm64 now with «fileSize: 8321575375». Glad to have it up and running now, thanks Xcode folks! ⧆ Previously, the machine under test had iphonesimulator 23B80 installed, and deleted via the Xcode 26.1 GUI prior to Xcode 26.1.1 being installed. The xcodebuild -downloadPlatform invocation for 23B86 was after sudo xcode-select -s /Applications/Xcode-26_1_1.app.