Does it matter if you or I agree?
http://www.vgchartz.com/yearly/2015/Global/ http://www.vgchartz.com/yearly/2014/Global/ and http://www.vgchartz.com/yearly/2013/Global/
all seem to to indicate that, unless you happen to be Nintendo, pretty 3D graphics are very much necessary (but far from sufficient) if you want to sell a lot of games.
edit: Mobile and social games like Clash of Clans, Candy Crush etc. are of course and exception. If you want make a lot of money in games and don't want to deal with high end 3D graphics, then that is the market you have to get into.
Many games are marketed and sold based on gimmicks and features, of which, great graphics is one of them and seems to work well. Unsurprisingly, much of the videogame industry has optimized for it. That doesn't mean that pretty 3D is necessary.
Of course i am assuming there is a story line or nice gameplay..
To give an example: my favorite game of all times, Ultima Online has at __best__, __meh__ graphics..I remember i got hooked before i even installed it, not because of the screen shots but the way the game magazine editor was telling his own experience how he got murdered while fishing quietly in a small town..