just going to add my 2 cents woth here
the use of demo when it comes to games or programs means that the software is finished and ready to be used . but the creator of the software is giving people a sample of the software(most demo software are missing some key elements making it so you would need to buy the full version) to use to see if they like or can use it then they can buy the full version.
this is not a demo this is more of a proof of concept.
for a better idea here is some light reading for you
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