I had the same issue and I took out carrier and inserted it many times until it worked 🤷‍♀️

I downloaded it on external hard and deleted another stuff on my Mac and re-expanded it on the Mac, thank God it finally got installed !

hey , i have the same issue , i have downloaded xCode from Apple Developer yesterday, and I expanded it on external hard cause I don’t have enough space for it in my mac , but it still expanding from 7 hours ago and it took about 60 GB and still expanding and taking space !! how much space that xCode need to expand ? i mean should I waiting or what ? please someone help me