I'll be the first to hate on DMC4 because it's a heavily flawed game, but it's still a fact that it was state-of-the-art in terms of graphics and gameplay when it came out.

Nero was a giant jump forwards in terms of gameplay and weapons like Lucifer and Pandora were extremely ambitious even if their execution wasn't perfect. There's a reason people latched onto that game for a whole decade and kept asking for DMC5 and loudly rejected when DmC didn't try to iterate on DMC4, even when it was clearly taking notes from it. Outside of Bayonetta 1 there wasn't anything on DMC4's levels for years, and if you see a deep action game after it the chances are they are directly influenced by DMC4. Ultrakill is probably the biggest example of this.