Hi @Mason Butts ,
Welcome to Q&A forum! we are glad to assist!
For files that are not synchronized, you can force users to view them online by removing the synchronization option. However, for files that have been synchronized to the local computer, unfortunately, SharePoint currently does not have the ability to delete them. The recommended method is to let users delete them.
If this is important to you, we recommend that you submit feedback on this issue. This is the best platform to let us hear from you. Microsoft values its customer feedback and a lot of features have been developed and suggested by customers via feedback. Moreover, we also appreciate your question, which can help make our products and services better for you and others.
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