I don't believe this at all. I think there's different tiers of journalism. One tier is going to publish "anonymous person says X" and that tier will be fast, sensational, and less accurate. Another tier is going to publish experts on the record and that tier is going to be slower, boring, and more accurate.
My perception of recent news tends is that sources that were in the accurate/quality tier are shifting to the fast/anonymous tier. In the short term their reputation plus speed and sensationalism will make them seem like the best of both worlds. In the long run people will just recalibrate their opinions of previously esteemed sources.
There absolutely are different tiers of journalism - but that's about quality and reputation of publication.
The Washington Post and the New Yorker have higher editorial standards than Fox News.
There are important stories for which it simply isn't possible to get an expert to go on the record, for all kinds of reasons.
What's going on inside Twitter right now is a great example. Anyone who leaks details with their name attached to them will clearly get fired, or sued, or both.
That's why good journalists quote anonymous sources. If they could get a reputable source to go on record instead they would obviously do so!
My perception of recent news tends is that sources that were in the accurate/quality tier are shifting to the fast/anonymous tier. In the short term their reputation plus speed and sensationalism will make them seem like the best of both worlds. In the long run people will just recalibrate their opinions of previously esteemed sources.