The company name is telling. Metadata is data about data. Data about you. They sell that. That's their whole business. That should be enough to not want to knowingly feed them more.
You think, "but I don't use Facebook or insta or threads, so I'm safe". Not so fast. Companies want to know how effective their ad spending is on meta products, so they integrate the Facebook sdk into their apps.
https://developers.facebook.com/docs/app-events
They are just over there sucking up data and selling it for billions. Oh and influencing elections and radicalizing our parents while their code infects apps and websites. The cancer comparison isn't far off.