I can't think of any official documents I'd be getting in Office file formats. Forms are mostly web ones or in some cases PDF, read-only documents are PDF. Maybe you can submit some documents or attachments in the Word format as a citizen but I wouldn't be surprised if PDF is already required anyway, or an image format for scans.
I'd be more worried about document interoperability between government agencies and other organizations such as companies that do work for the government. The government could of course mandate contractors to use an open source office suite which would extend the need for training to those companies.
Also, I've seen some orgs make heavy use of Office formats in terms of e.g. surprisingly elaborate formatting, document history and comments, and although I haven't tried to use those in LibreOffice, I wouldn't be sure it supports all of those in the same extent some people have learned to use them in Office.
I'd be more worried about document interoperability between government agencies and other organizations such as companies that do work for the government. The government could of course mandate contractors to use an open source office suite which would extend the need for training to those companies.
Also, I've seen some orgs make heavy use of Office formats in terms of e.g. surprisingly elaborate formatting, document history and comments, and although I haven't tried to use those in LibreOffice, I wouldn't be sure it supports all of those in the same extent some people have learned to use them in Office.