There's a non-zero chance that NDAs could use to shield bad people and/or bad companies from criticism, but often they're just used to stop spreading info to competitors, stop spoiling stuff, etc. Not crediting someone is usually scumbaggery, but in case of VTubers, they usually get doxxed within a week, especially big names and those that used to be big previously.
They're trying to get the content off from the Fediverse, due to them only having corporate ads. (Only slightly preferable to the conspiracy theories advertised on Twitter.)
Remember always use flared stuff!