Honestly im beginning to think it was the right idea, considering it eschews lots of the casualized shit most modern shooters do and prefers to instead be a hybrid of new+old, but with more emphasis on the old.
The gameplay emphasizes movement above all else, which is opposed to modern shooter philosophy which is slow and steady, take cover and pick off enemies one by one, taking a breather if your health runs low to let it regen.
Doom 4 has no regenning health so you have to hunt for health pickups and utilize the glory kills. It has you look for key cards to open doors in large winding stages, and it's monster encounters are all about frantically staying on the move, since enemies hunt you down. I can see the casual CoD kiddie or reviewer calling this game too hard or unfair, and thats besides all the optional shit (thats on by default) like a compass, objective markers, and a glow that highlights stunned enemies for takedowns. All of which can be toggled off.
overall, as far as the single player goes, it's pretty good. Everything Duke Nukem Forever probably should have been as far as gameplay goes.