New M1 Macbook pro shipped with less memory than advertised

No adjustment or accommodation of any kind is forthcoming, and my example was deliberately hyperbolical.

As I said, if you work through the computations and the footnotes on the Apple Web site, you will come to understand that you have received what was promised. It formats to less, and that is the way drives have been sold -- for as long as there have been drives. No regulations have been violated.

If you are not satisfied with that FOR ANY REASON, or no reason at all, you may return your purchases direct from Apple for a full refund, provided you do so within 14 days of receipt.

You have 14 days to return any item you purchased DIRECT from Apple if it falls short of your expectations for any reason.

There is a whole lot of fine print on the web site regarding computation of effective drive sizes based on marketing speak vs programmer speak. Read all that and work through the computations and you will see Apple has covered their bases. You got the promised about 500-ish drive.

No one is going to email you an additional 18GB.

This is normal and is how HDDs as well as SSDs are rated and have been rated ever since their inception. My MacBook Air M1 (8GB/512GB) has approximately ~500GB showing on the SSD as it's capacity.

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