Simulator runtime stuck "Deleting"

Do you se anything relevant in ~/Library/Logs/CoreSimulator/CoreSimulator.log ?

Please run 'sudo sysdiagnose -q' and 'xcrun simctl diagnose' after reproducing and provide the resulting tarballs. Debug logging can be enabled via defaults write com.apple.CoreSimulator DebugLogging -bool YES (and can be later removed with defaults delete com.apple.CoreSimulator DebugLogging).

I am trying to resolve similar issues.

Note that first I explicitly deleted unneeded runtimes using Xcode 26.6 Settings / Components. But listing them with xcrun simctl shows them in that (Deleting) state.

I managed to remove some of them with this procedure:

xcrun simctl shutdown all
osascript -e 'quit app "Xcode"' -e 'quit app "Simulator"' 2>/dev/null
pkill -9 -f SimLaunchHost

V=/Library/Developer/CoreSimulator/Volumes
B=/Library/Developer/CoreSimulator/Cryptex/Images/bundle
while read -r vol bundle label; do
  [ -z "$vol" ] && continue
  echo "▶ $label"
  if mount | grep -q " $V/$vol "; then
    sudo diskutil unmount force "$V/$vol" >/dev/null && echo "  ✓ unmounted runtime volume" || echo "  ✗ runtime volume unmount failed"
  else
    echo "  · runtime volume not mounted"
  fi
  if [ "$bundle" != "-" ] && mount | grep -q "$B/SimRuntimeBundle-$bundle "; then
    sudo diskutil unmount force "$B/SimRuntimeBundle-$bundle" >/dev/null && echo "  ✓ unmounted parent bundle" || echo "  ✗ parent bundle unmount failed"
  fi
done <<'EOF'
watchOS_22S99    726954A0-4841-4185-99D3-DF85C6E03CC1 watchOS 11.2
watchOS_22R581   55C00A55-29D7-4916-BFB1-C281F91E31F5 watchOS 11.1
watchOS_22T250   F105BB7C-6B2D-4E6C-B310-4B9C34176917 watchOS 11.4
watchOS_23S303   -                                    watchOS 26.2
watchOS_23T239   -                                    watchOS 26.4
watchOS_24R5289n -                                    watchOS 27.0 beta (24R5289n)
watchOS_24R5305f -                                    watchOS 27.0 beta (24R5305f)
tvOS_23L470      -                                    tvOS 26.5
tvOS_24J5289o    -                                    tvOS 27.0 beta
EOF

echo; echo "Restarting simdiskimaged…"
sudo killall -9 simdiskimaged
sleep 45
echo; echo "── Still listed as Deleting ──"
xcrun simctl runtime list | grep Deleting || echo "none 🎉"
echo "CoreSimulator mounts: $(mount | grep -c CoreSimulator)"

But it does not catch all of them with this log errors looking relevant:

% log show --last 30m --predicate 'process == "simdiskimaged"' --style compact | grep -E "Could not remove Mobile Asset" | tail -6
2026-10-20 22:19:47.847 E  simdiskimaged[1837:7a12] Could not remove Mobile Asset runtime bundle: /System/Library/AssetsV2/com_apple_MobileAsset_appleTVOSSimulatorRuntime/c355f70517ca008a3cfc8f7ba236baed0b3dff9f.asset/AssetData/044-89169-079.dmg with error cannotResolveMobileAssetID
2026-10-20 22:19:58.372 E  simdiskimaged[1837:7a12] Could not remove Mobile Asset runtime bundle: /System/Library/AssetsV2/com_apple_MobileAsset_iOSSimulatorRuntime/cc1f035290d244fca4f74d9d243fcd02d2876c27.asset/AssetData/096-69246-684.dmg with error cannotResolveMobileAssetID
2026-10-20 22:20:09.375 E  simdiskimaged[1837:7a0c] Could not remove Mobile Asset runtime bundle: /System/Library/AssetsV2/com_apple_MobileAsset_iOSSimulatorRuntime/b7ebcb41b53f3ba74bbda35337320e05342e1996.asset/AssetData/044-32102-001.dmg with error cannotResolveMobileAssetID
2026-10-20 22:20:15.481 E  simdiskimaged[1837:7a0c] Could not remove Mobile Asset runtime bundle: /System/Library/AssetsV2/com_apple_MobileAsset_iOSSimulatorRuntime/4d6f1d5e94817785365ca3e550933440a004fcc1.asset/AssetData/044-04621-122.dmg with error cannotResolveMobileAssetID
2026-10-20 22:20:22.486 E  simdiskimaged[1837:7e16] Could not remove Mobile Asset runtime bundle: /System/Library/AssetsV2/com_apple_MobileAsset_iOSSimulatorRuntime/3ee34d773407290b674484df946712d331558e17.asset/AssetData/092-10337-196.dmg with error cannotResolveMobileAssetID
2026-10-20 22:20:28.511 E  simdiskimaged[1837:7a12] Could not remove Mobile Asset runtime bundle: /System/Library/AssetsV2/com_apple_MobileAsset_iOSSimulatorRuntime/6fb1e5fe25ee1c372f7116516e615c556906bd4e.asset/AssetData/090-44150-318.dmg with error cannotResolveMobileAssetID

% xcrun simctl runtime list                                                                                                       
== Disk Images ==
-- iOS --
iOS 18.2 (22C150) - DCFE462E-9BC5-4EF2-A482-FD4AB0A490AF (Ready)
iOS 18.4 (22E238) - 17A8D10D-11F5-476C-A4EE-7CAB10694D29 (Ready)
iOS 18.1 (22B81) - 442F2EA2-CB78-4D2D-863E-CEF5A9EDD7B1 (Ready)
iOS 18.5 (22F77) - 544E42CD-C636-4194-A5A6-A5F944AF05BC (Ready)
iOS 18.0 (22A5346a) - 09C5925F-CBF8-4C66-846E-54AF03EFA49F (Ready)
iOS 16.4 (20E247) - 4330ABF8-DF3A-4C01-A6C0-3B1810FDD02A (Ready)
iOS 17.5 (21F79) - FCBFBD6A-9446-4EF1-8A52-7963BC057FD3 (Ready)
iOS 18.0 (22A3351) - 57416A42-E1C4-4589-BB53-1A6F58F16C50 (Ready)
iOS 26.5 (23F77) - 59EAC083-A43F-40F0-9A97-B7BF95E5FC61 (Ready)
iOS 15.5 (19F70) - 7A23AB1F-9A95-4888-BACA-A7FAC3D2B3A0 (Ready)
-- tvOS --
tvOS 26.5 (23L470) - AD7A9989-65AF-4211-B3C1-BCB78BE43891 (Deleting)
tvOS 27.0 (24J5289o) - 000BAB81-BCB8-4E47-A7B6-58C5358C693A (Deleting)
tvOS 18.2 (22K154) - CC0C1824-94E0-4EE3-AFD0-51C02CCE8B1E (Ready)
tvOS 18.1 (22J578) - 3F4960BB-B099-4FD4-A187-5E8826F82D8D (Ready)
-- watchOS --
watchOS 27.0 (24R5289n) - EA932456-F6F2-48A7-97BA-6B908243CB78 (Deleting)
watchOS 11.5 (22T572) - 39D1C278-FFBA-4072-A01A-B1CE52DF2AF0 (Ready)
watchOS 26.5 (23T570) - 11B1E8B0-C46E-47A1-ACB8-9FE68C58E20E (Ready)
watchOS 26.4 (23T239) - AEE96F99-ED10-4FEC-999A-BD4051CCDC36 (Deleting)
watchOS 26.2 (23S303) - F7064EB1-5494-4CC9-A4F0-95AC61548361 (Deleting)
watchOS 27.0 (24R5305f) - 668E00B0-F4FF-49FD-B8D9-266099D59209 (Deleting)

Total Disk Images: 20 (117.9G)