MrtnFbg's answer inspired me to read more about redirections of streams. So I read about Linux STDOUT STDERR. In this specific case when I run this command, there is an output and there are some errors. Since I ran this command on terminal and on terminal the STDOUT and the STDERR is the console itself hence, I was seeing both the json and the errors. I now don't see an issue with the Xcode 13 or the command itself. I need to update the way I am consuming this command. Since I am interested only in the output of the command hence it should have been xcodebuild -list -json 2>/dev/null where I am redirecting 2(the error stream) to a file that just eats up whatever it gets(the /dev/null file)

As seen in the spindump, Pendo was blocking the main thread. Updating it to latest version thankfully fixed this problem. PS: Pendo seems to use AsyncDisplayKit internally and there is a ticket for this there https://github.com/TextureGroup/Texture/issues/2029 Cheers!

I can see that one of the pods that we use Pendo is there in stack trace. I will try updating it to latest version and see if it fixes the problem