Leonard Nimoy created the Vulcan salute.
The famous Vulcan salute was devised by Spock’s actor, Leonard Nimoy. The actor said he decided that Vulcans were people who oriented themselves with their hands. The salute became so famous that it has even become an emoji. When the actor passed away, social media flooded with people recreating the Vulcan salute in Nimoy’s honor.
Of course, this hand gesture means "read between the lines"...
He came up with it for the character. He's the reason it's in the show. That's all that anyone needs to know. Pointy ears weren't a new thing, either.