Slang/incorrect use. Used to show emphasis. A better use would be: “I literally have the best intel mac and the m1 air beat it” In that case it is literal. OP

Slang/incorrect use. Used to show emphasis. A better use would be: “I literally have the best intel mac and the m1 air beat it” In that case it is literal. OP probably just switched it over to a case where highlighting literal ownership is superfluous.