I'll grant you some things.
1. The mainstream news sources have messed up lots of times. (I would argue that their success rate is very high, though)
2. The mainstream news are largely ad-supported and therefore their entire line of work is a bit of a minefield of conflicts of interest.
That said...
They are not perfect, but comparing them to a disinformation merchant like Alex Jones is an absolute farce.
Stories at "real" news organizations are vetted by multiple members of the staff. They make corrections. This cannot be said of wack jobs like Alex Jones. They are not even in the same league in terms of good-faith effort to get things right.
Bound by whom? Where is this obligation written?
Who holds them to it? What are the consequences
if they break it?
One, institutions like the NYT and WSJ bank on their reputation as purveyors of the truth and as institutions with rigorous reporting standards. They rely on that in ways that Alex Jones does not. He relies upon being shocking and edgy.
Two -- and perhaps more tangibly -- traditionally in mainstream media, reporters caught fabricating stories or otherwise being unethical essentially forfeited their careers.
You can see both of those factors at work in the story of Jayson Blair, a reporter who was caught fabricating stories for the NYT.
https://en.wikipedia.org/wiki/Jayson_Blair#Later_career
https://www.nytimes.com/2003/05/11/us/correcting-the-record-...
Yes, the NYT was duped. Embarrassingly. But the system worked. They conducted a pretty intense internal investigation to catch the guy. They caught him. They set the record straight. They admitted they screwed up. In that one instance they displayed more journalistic integrity than you'd see from Alex Jones in a lifetime.
And what happened to Jayson Blair? As I said above, his journalism career was over.
You can point out problems with "traditional" news organizations, and I'll agree with many of them, and they are still miles better than conspiracy hacks with zero journalistic scruples.