Is it no longer possible to gift via e-mail on Steam?
I know it was previously possible on Steam to buy a game / software as a gift and let Steam send the game code to someone's e-mail address. Now all I see is the ability to select one of my Steam friends to send the game code to.
It looks like in May of 2017, they retired the functionality of gifting via email. A Steam Forum post of someone who had the same question as you, led me to a Steam Blog which states:
Steam Gifting will now be a system of direct exchange from gift buyer to gift receiver, and we will be retiring the Gift to E-mail and Gift to Inventory options