There are, in fact, at least two major reasons for the decline of the MSM.
One of them, of which we are well aware, is their incredible bias, willingness to lie, carelessness about reporting the facts, and steady dumbing down of the product.
The other is simply the growth of the internet, which is stealing their advertising revenue, more or less regardless of how good their product is.
Not much they can do about the second problem. And not too much, possibly, that they can do about the first. Because their readership at this point is probably mostly leftists, the last ones to leave the sinking ship. If they go hard right, they may drive away a lot of current readers without gaining new ones.
Their fault, of course, for polarizing their audiences in the first place. To return from ideology to economics, their problem was that they had a MONOPOLY ON THE NEWS, and monopolies are always economically destructive in the long run, as soon as some clever entreprenteur figures out a way to make an end run around them. That turned out to be Steve Jobs and Bill Gates, and now the MSM is reaping the fallout of having pushed their monopoly to the limits because of the usual pride and blindess--hubris--that having monopolistic control of something produces in the operator.
The handwriting is on the wall.
It's all over but the "excessive taunting" penalties.
It's not that the mainstream media was too leftist -- as much as the world of writing got much better -- without them. The kind and quality of writing we see on forums like these exceed the best mainstream media has to offer -- that "their" best want to play in the bigger pond too, but quickly learn that the waters run more deeply and quickly than the protected and restricted enclaves of the mainstream publishers.
Very few of them can make the transition -- of writing to everyone instead of just the approval of their editor, who used to preen themselves on that absolute power regardless of whether the article was intelligible to anybody else.
Schools and universities are losing their authority for the same reason -- when students realize that the power is not in writing for the purpose of impressing the self-imposed centralized authority -- but in being able to communicate effectively with everyone else!
That is the real power of information and communications -- that has the old establishment on the verge of extinction.