It is inexcusable when game demos aren't released in a timely fashion. It took three months to get a Prey trial, not to mention how long it was before we saw a Ghost Recon: Wildlands sample.
And social interaction.
I think any product that you cannot return for a full refund (Games and Music mostly) you should get to sample before you buy.
Multiplayer games have plenty of demos called "betas".
I think demos are less needed nowadays but what I don't like is demos tailored to sell the product and misrepresent the game. Example is Brütal Legend. That demo/opening portion was epic, funny, action oriented and a big lie. Once you got out into the open world is was crappy RTS focused, barren mess. I was incredibly disappointed.
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