Here's the proof.
Bethesda Softworks revealed yesterday a teaser trailer and a few screenshots for their upcoming Fallout 4 game, and I was surprised that game looks worse than an open world game from 2007.
Here's a couple images comparing Fallout 4 (top image) to S.T.A.L.K.E.R.: Shadow of Chernobyl (bottom image), which was released in the early part of 2007. Both of which are open world games.
What's ironic is S.T.A.L.K.E.R.: Shadow of Chernobyl wasn't considered a good looking game back in 2007. I understand the "Fallout" series has never featured state-of-the-art graphics, but that series has never looked that outdated.
Fallout 4 better feature state-of-the-art gameplay and a very dense environment to make up for the low quality graphics...