Honestly OP, I don't mean to sound rude by this, but if you couldn't tell that this game would be repetitive to you in a negative way after a couple YouTube videos, then I think you just did yourself a disservice in purchasing it.
This game is getting high praise because of the repetitive gameplay loop. It's satisfying, self aware, crunchy, gorey, fast, and brutal sci-fi horror cheeze. If circle strafing for hours while cycling through weapons with a good level of difficulty sounds like a snooze fest after a while, then it's simply not for you.
Also, the FOV can be changed, the difficulty can be changed, and the AI is more than serviceable for this style of game. It's actually quite excellent in the way they flank, chase, and retreat. The game is about aggression and in your face encounters. The AI does it's job admirably by constantly putting pressure on the player. Don't know what to tell you there.
No one, including ID software, has been vague about what this game offers. I feel like you duped yourself. Sorry it doesn't click with you though, I know how that feels when you don't like something a lot of people love. For me, it's the Witcher 3. I think that game is boring garbage. I'd rather shoot demons in the fucking face for hours. That return to simplicity and old school gameplay design is what makes this game so refreshing and special.