This is wrong. Wi-fi direct has always been possible with Android phones. Android even supports wi-fi direct connections simultaneously with wifi ap connections. Abdroid also supports the new wi-fi aware, euch simplifies initial contact via broadcasts.
I am not sure why the device manufacturers wouldn't implement it. Maybe they target iPhone first as the more premium users (which might only be true in the US), and then think they cannot support that feature for lowly Android users.
If enough devices supported this, Apple may be incentivised to follow?