No.
You have a NON-TRANSFERABLE license.
This means you cannot give it away.
And even if you refund the game, the license is simply deactivated, it is still tied to the account.

You either buy your friend their own copy as a gift or you send them a steam wallet gift card so they can buy it themselves.

Your copy is forever yours.

If I were a developer I'd like to make money off my work. Wouldn't make very much if my customer base were just sharing copies.

I'd rather pay $5 for a game and keep it, than pay $20 for the same game so I could maybe give it away someday.

引用自 MysticSoul1472：

So I was talking to a friend about a game I want them to try that I already finished. Unfortunately, they can’t buy the game due to budget reasons. Therefore, why not be able to gift games we will not be playing anymore? If I finished a game 100% and I know I won’t be playing it again, I could send it to a friend who wants to try it. I already payed for it and it would just sit there accumulating dust; it would basically be like paying for a brand new game for them.

So where does the money come from to give to the developers as surely they would want to get paid for that second copy. Not to mention if someone's account is compromised, their games transferred away.

引用自 MysticSoul1472：

Therefore, why not be able to gift games we will not be playing anymore?

Cause businesses want to stay IN business.

引用自 MysticSoul1472：

Gift Owned Games

You don't own any games. You own personal use licences permanently attached into your account.

Devs are given millions of dollars to make games by investors who expect a return on their investment. Games need to make enough sales to give returns that satisfy investors. If they don't the investors will put their money elsewhere. Letting people resell their licenses could eat into profits enough that investors will put their money into other things with higher returns. That could be games that use subscription models, games that rely more on micro-transactions, games that are so popular that people will still buy them day one rather than wait for resales to pop up, or even into non-game products.

The consequences could easily be less variety of games as only the absolute biggest money makers are given money or less games are funded in general, or even more aggressive monetization schemes that drain players of even more money while still not allowing players to benefit much, if at all, from reselling. Part of the appeal of digital downloads for publishers was that it prevented reselling and we even see some games with physical copies still limit access via a one-time use code that registers the game to an account. There is no reason to believe that companies wouldn't find ways to avoid reselling even if it were allowed on Steam.

Also I'm aware that this is focused on AAA games and the like, but smaller indy devs could be limited by reselling too, especially if they are using sales of previous games to fund newer ones.