I reckon context is important here. If someone is chewing you out and you give a thumbs up it could be passive aggressive. But yeah in a business context I use it pretty frequently to acknowledge the message without needing to add to the conversation.
It means OK or acknowledged. It does not mean “fuck you”. People who think it means “fuck you” are the only people having a bad time with this.
I reckon context is important here. If someone is chewing you out and you give a thumbs up it could be passive aggressive. But yeah in a business context I use it pretty frequently to acknowledge the message without needing to add to the conversation.