I facing this issue too. This is because the latest xcode only support until iOS 15.2 sdk, but my phone's iOS version is 15.3. Thus, xcode is downloading the iOS 15.3 sdk from your phone that's why takes time (I knew the message is not saying that)
However, I do some testing and it works for me.
Get the iOS 15.3 sdk (is 10BG!!!) from my friend xcode's Devices Support iOS folder /Users/***/Library/Developer/Xcode/iOS DeviceSupport and paste it to yours one.
Downloading the iphone OS device support file from https://github.com/filsv/iPhoneOSDeviceSupport/blob/0e8ef7bc51b982304ed3258454f88ae2d5615ac7/15.3.zip unzip it and paste it in /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport
Restart Xcode
Build success without waiting.
edwinwong90
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