I agree with the above that the vast majority of AAA games these days, developers are restricted by the money men who want all their games in safe hands:-
Guns
Established Brand
Micro-transactions and DLC
The above are always at the forefront of many games these days and it's inevitable that it's going to get boring. Take nearly every fast shooter since Titanfall.......Titanfall introduced a new jumping system and low and behold, many more fps games jump on the bandwagon because Titanfall sales were high. That mechanic is now tiresome due to saturation of it within games.
You are like me, whereby you hope that every new game gives you that 'old spark' you used to get from games and are mostly left disappointed.
That doesn't mean there aren't games out there that still capture my interest beyond the first couple of hours. The Witcher 3 keeps my attention. Not that it does anything particular new, just it's a solid game that looks amazing with a great story and characters I really warm to.