It is plenty of grind in the traditional sense but NOT mostly RNG. This is a terrible and unfounded misconception. It's possible to rely on RNG to progress in this game but by and large an objectively bad idea leading to heartache and frustration.The endgame with light levels and getting raid/Nightfall strike-ready is mostly grind and RNG. If that doesn't sound like your cup of tea, it might be time to bail.