The market is becoming more casual. The game should first and foremost be accessible and understandable to ANY player and must lead them to the end without much effort. As a result, genres such as quests, adventures, old-school RPGs, and hex-based wargames have almost disappeared or mutated.
The pace of technological development is now much faster than it was 10 years ago, which also largely determines the focus of games on graphics. And, let's face it, players have also become more demanding, and far fewer people will play a game with poor graphics but good gameplay than will play a game with good graphics but poor gameplay.
P.S. This is just my IMHO; please don't criticize me too harshly, but I am always happy to hear reasonable responses (and criticism).