A Microsoft file hosting and synchronization service.
Hello,
Unfortunately, there's no way to prevent this via settings. We are all on the same boat.
If someone knows your email address, they can share files with you by sending it to your address in OneDrive share feature. Or if they send you a link and you click on the link, the file will also show up on this tab. For example, me helping other users on this forum, and often users share certain diagnostic log file via a OneDrive link, it all end up showing up in my "shared" tab in OneDrive too.
It really serves as more of a record. The file doesn't live in your oneDrive or your device, doesn't take up any of your storage. It serves as a share record list. Yes, you can hide or report it, those are the only options now until Microsoft comes up with more features to allow complete removal, etc.
Consider sending a feedback to the product group. https://feedbackportal.microsoft.com/feedback