Although Lua is a great language for scripting servers in, it is also not widely known by many from other multiplayer mods, (aside from maybe MTA:SA). Adding additional language support commonly used in other GTA multiplayer mods might help attract more scripters to create servers for IV:MP. I personally would love to create one myself if there was Node.js/Javascript support. A lot of users who used to script for SA:MP would probably also go wild if they could use Pawn. Having multiple languages isn't unheard of, and a few other GTA multiplayer mods have successfully accomplished this.