Hello Stryderis,
Thank you for your swift response.
It seems that you're on a Windows 11 version right now. Have you reinstall OneNote from the link I have provided?
To better isolate the issue can you please create a new Windows user profile and try to export notebooks from there? Please give it a try because there's a possibility that your Windows profile is corrupted due to a Windows upgrade.
Click here: Create a local user or administrator account in Windows
We look forward to your response on the results. If you have other clarifications about this matter, you can get back to us by replying to this post.
Sincerely,
Juhn Jac,Consumer M365 Forum Moderator