Beside his prolific crypto bro arc and attempts at effective altruism, he did very little during his tenure as CEO and let the company stagnate during it's most lucrative years. On top of that, his moderation double-standards were as bad as Musk and he even went on to admit that Twitter in it's current incarnation is a mistake. He did a good job of building a company from nothing, but struggled to turn it into anything profitable.
Twitter was losing a billion dollars per year when Jack left as CEO. He may have not run Twitter into the ground, but neither has Musk so I'd argue it's a moot point.
I'm not trying to compare Jack Dorsey to Larry Elison, but my point is that Elon exists somewhere between these two on the axis of "deliberate ruthlessness" and "bumbling incompetence". For Twitter to be profitable, it has to be run like a business instead of a parody of the tech industry.
> Twitter was losing a billion dollars per year when Jack left as CEO.
He left in 2021 when they lost $220M (not a loss of a billion dollars) because of an $800M settlement which means they -technically- made a profit of $580M (very much not a loss of a billion dollars.)
If you're thinking of 2020, that does seem to have been a $1.1bn net loss but that's somewhat balanced by 2019 which was a $1.4bn net income (according to [1])
> He may have not run Twitter into the ground, but neither has Musk
Musk has added a $1bn/year debt servicing obligation - the company will have to make $1bn/year profit just to reach net $0. I don't think there's any scenario available where this isn't "running it into the ground".