Nothing you said contradicts GP, who didn't claim Elon discovered anything. Elon did recently demonstrate what has been known for a long time - but not widely believed.
If I remember correctly, he reduced the content moderation team, which led to an increase in hate speech, misinformation and CSAM. That's why big advertisers left and revenues crashed.
He then told those big advertisers to piss off and refocused his advertising business on smaller customers, which is why he doesn't need so many ad sales people any more.
Perhaps he should hire some developers and data scientists to better automate content moderation.
He also did fire a lot of sales and account managers in those first weeks. There were advertising customers in the news who were no longer purchasing ads because they literally didn't know who to contact any longer.
The first line is the narrative of the MSM that's in bed with government censors and hate that it's no longer controlled by political interests. It is also directly contradicted by independent studies commissioned by Twitter. But speaking of "misinformation", people tend to parrot what they hear whether it's true or not. Thankfully on Twitter that is less effective, thanks to community notes.
Advertisers leaving is a combination of instability caused by Musk's impulsive decision-making, uninformed bandwagoning based on the perception projected by aforementioned MSM and parrots (AKA peer pressure), and the state of the economy combined with the above forcing them to reevaluate their investments. Advertisement revenue has been dropping everywhere as it turns out.
So, you agree with the GP but also think it's a conspiracy that brands care about their brand perception?
You may ot even be wrong about "peer pressure", but that's how so much of the rest of the world works. Part of the downturn isnt based on economic logic but peer pressure: "BigCo is sizing down so we should too!". The aforementioned brand perception is the exact same way, but based on the consumers over the company. The Stock market as a whole is literally based on speculation.
As long as stuff is run by peoople, people will influence other people to make decisions based more on gut feelings than raw facts.