I agree, they are being way to harsh on it. Titanfall had almost no story or co-op modes, and a multiplayer mode missing basic features like private matches a launch yet got way better scores!!
And it's not like you are paying more for Destiny either. Destiny easily gives you 50-100 hours of fun if you really get into it, and its not like they are charging you a fee as a MMO would.
Now I'm not going to pretend that Destiny is perfect, but it is a far cry from the poor reviews it has been getting!
Here is a list of my pros. and cons for the game.
+Diverse enemy types
+Good loot game
+Lots of fun Co-op activities
+seemless conection to other players
-frustrating chat system
-no private matches
Destiny is indeed far from being perfect... My personal score is 9/10 for the game based on the hours and quality of fun I've been recieving. I treat the game as an investment... the Return on my investment in terms of the hours of fun Destiny has provided me compared to other games I've paid a similar price to is 9/10. Opinions vary and I've had fun playing age of wonders 3 for example which got better reviews than Destiny and I'd still rate 8.5/10.
On a personal level, I can understand how someone can rate the game 6 or 7/10 because it is the fun factor for them... For a professional reviewer however, who is supposed to rate the game without bias, trolling and with adequate research and analysis on the quality of the game; having a 4/10, 5/10 or 6/10 is just unacceptable.
To take an example: Gamecritics rated Destiny 45/100 but gave Wolfstein 100/100. Not to say that wolfstein, released a couple of months ago for the same price was a bad game but the difference in rating is just messed up.
I am a Gamer... I play games and not consoles. I have a PC and Console on which I game... I like games. End of Story!