The problem with idTech games is that they are not the best visual example that other developers aspire to, sure they run damn fast, but that's because of the huge sacrifices they make in visual complexity. Wolfenstein 2 for example has low polygon count for almost everything, even main characters. Facial animation is bad, Texture resolution is moderate at best, scene complexity is moderate as well, no convincing water or cloth simulation, shadow resolution is also moderate. Most areas are corridors and closed spaces. So yeah, by 2017 standards, the game doesn't look impressive at all, it's serviceable and sometimes good looking but nothing more.