Why hasn't keyboard and mouse support not implemented?

It is already proven that the ps4 is capable of it, some games are playable with controller and keyboard and mouse. We don’t all have beefy computers to play games like this so why not at least let console players experience keyboard and mouse gameplay. Aiming can be a nuisance especially in fast paced shooters like borderlands. I believe the devs can work around a solution to whatever technical limitations the game has if ever it does have any. It’s been years but I’m still crossing my fingers.