The RPG is also tricky as everyone seems to have their own definition of it (and yes some people here have 'defined' it but that doesn't mean that definition is right). So I much prefer FO4 to Witcher 3 on a personal level but looking at it in a somewhat objective view point (if that is possible) W3 just seems prettier, more polished, and overall a better game. Only games I tend to like are where you can make your own character (with various levels of freedom) and RP them as you like (again more or less depending on the game) with a focus on the fantasy genre. Playing Geralt is like any other game where the main character is completely defined for you - and I have never liked any of the games (Assassins Creed, Tomb Raider, etc.).

Playing Geralt is even worse than playing Shep in the ME games - at least there you had some wiggle room. I personally prefer FO4 because the one thing that prevented me from enjoying W3 was lack of character freedom. Rather different games to be comparing but even though I could not get into W3 I would say its the better game overall when looking at graphics, writing, characters, story, atmosphere and the like.

Witcher 3 vs fallout 4