Agree with Gorath.....
Listen up, I don't care how badly coded or optimized or whatever, all a program can do is run your system to the max limit of it's capabilities...PERIOD. I can't change fan profiles, it can't make a CPU or GPU run over what is set in Bios or exceed maximum performance. What it can do is MAKE IT RUN AT MAXIMUM PERFORMANCE for the computers set-up. So if you have a system set up and cooled properly then if you run it at max capacity, it will NEVER overheat, because in a properly set up system, your cooling system will be designed to handle it. All stock coolers are designed to cool the card/chip at max capacity for extended lengths of time. If you overclock you often need to change those coolers out, or if you don't want them to exceed a certain personal point, then you will have to change them or if you have bad air flow in your system you may need better coolers...
The only thing a game like DAI that is badly optimized in many ways, but also highly intensive in graphics and details, can do is expose systems that have failing coolers, running with coolers below standard for their set-up, poor air flow, or are badly in need of cleaning. Period... So yeah, it is the game...only so far as it is exposing issues that you already have, but because you aren't pushing your system to max you never see.
Think of it like this....take your car, put it on a speed track, put the pedal down to the floor...something will probably eventually break, overheat or otherwise give issue...it isn't the tracks fault, it is just that the driver finally pushed it enough to show up the problem.