@dshafik it took like a half hour just for me to extract the xcode .xip (on 2018 Mac mini) last time I touched it

It's a machine that has entirely solid-state storage and is somewhat modern. (Unless somehow the built-in storage goes through USB 2.0 ...)

I still don't get how Apple got fat, slow bits masquerading as "Xcode".

I don't think even this new ARM chip of Apple's is going to do anything about it.