Is there a way to lock down table formatting and allow text updates in a public doc?

You could insert text form fields where you want editing to be allowed and then apply forms protection.

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional

You could also forgo the content controls and apply read-only restrictions to the document, tagging as exceptions just those portions (even at the individual cell level) you want to allow people to edit.

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Cheers,
Paul Edstein
[Fmr MS MVP - Word]

For more options, take a look at http://gregmaxey.com/word_tip_pages/repeating_data.html. But note that the article focuses on repeating content.

__________________
Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional