They kind of are though. If they've chosen not to be in a management position, they have chosen not the have all the context around decisions, nor devote their mental energy to evaluating and making managerial decisions.
Qualified isn't necessarily the right term, but you can't be the leader only when its convenient, that just won't work.
TBF, it sounds like he's barely involved (He does live in Brazil after all), and he just uses the intercept as a venue to post articles to which he has full editorial control.
If he doesn't actually have any ownership, nor a title, just a contract that says he can publish articles in exchange for the use of his name, then, yeah, they can tell him whatever they want.
Instead of applying the corrections or pulling rank and saying that he's the founder and wants his article to be published despite the damage it might cause to the paper's reputation, Greenwald threw a tantrum, flung a bunch of accusations at the editor, quit, and took it all public.
The Intercept said it had no doubt that Greenwald would "launch a new media venture where he will face no collaboration with editors — such is the era of Substack and Patreon."
"In that context, it makes good business sense for Glenn to position himself as the last true guardian of investigative journalism and to smear his longtime colleagues and friends as partisan hacks," the Intercept statement reads.
"We get it. But facts are facts and The Intercept record of fearless, rigorous, independent journalism speaks for itself."
https://www.washingtonpost.com/media/2020/10/29/glenn-greenw...
Forget about the Intercept for a second and try it like this: Imagine a tech startup cofounder wanted to remain in the trenches instead of managing others. Then she's accused of not respecting the management that formed around her. Yeah, no shit, they have to earn it. And it takes a lot of fucking nerve to tell her "you didn't give yourself a management job before now, even though you were at one point free to. Therefore you're unqualified to make this specific managerial decision, even though you deliberately created a contractual route to retain that power over those certain choices even if it isn't your day-to-day job."