Why not have difficulty that scales depending on the number of players?
How many players have a group of friends who also play the game and are free at the same time and are wiling to dump 2-5 hours into a single mission with the possibility of total failure?
It's just a little silly to safeguard one of the best parts of the game for the sake of maintaining it's purity in the eyes of the 15% (at most, I'll have to check trophy percentages) of the playerbase that experiences it.
22%
Scale difficult how? I agree it needs to become harder to solo or less players to estimulante them to play cooperative.
Raids needs puzzle and boss fights that requires a full foreteam to play syncronized talking with each other.
That is what Destiny means.
If you want a solo experience there are dozen of the games in the market that are better in that aspect.
You buy Destiny knowing it is a cooperative experience.
You read and talk with gamers that played Destiny and found it absolutely boring... a deception... but when you put this same guy to play with a fireteam then it changes his mind to the point to says it to be one of the best experiences in their game life.
That is Destiny.
Forget the borefest solo... plays in teams... talks, laugh, joke, distress, make friends (even if online), cry, hate, etc... do everything with others in the same fireteam.
Destiny is absolutely magical.