Musk got rid of the people who owned the relationships with the brands and agencies that drove the ad revenue. Burning those relationships plus getting rid of content moderators made sure advertisers were very skeptical of being on the platform. Then there's the GARM lawsuit causing that tiny org to shut down, suing another non-profit for point out brand safety issues, etc.

It was Musk's actions.

Firing the teams that manage moderation and letting Coca-Cola and Nike paid for ads show along side Nazi and porn content, basically allowing the ad side of the platform to go to shit, is actually much of the reason for the advertiser exodus.

You can't tell easily without informations from inside.

I'm starting to see ads during Great Replacement and Kill The Brown People threads on Twitter. It's not pushing me towards buying a product or clicking an ad.