Sane here , got it yesterday and no issues

Depends on what fps you play on. Locked at 30 fps 3ish hours or so. 2-2:30 if you lock it at 40 fps .

Mine has been stuck in “packaged” since launch day

It sounds like you got a the regular 1TB model by accident. Valve wouldn’t just replace the shell without telling people. Especially if you paid the extra $$…