Font book not launching

1 - Safe Mode ( which as already been attempted 0 Good Work there 😀 ) will also eliminate Third Party Software, extensions and drivers from loading.

It will only load the Minimum amount of Core Apple Processes to allow the the computer to function at a reduced Level of Performance 

2 - If not - there could be something in the main User Account playing up. To further isolate this - Set up users, guests, and groups on Mac. Then log out of the Main User account and log into the dummy account and test again if the issue persists.

3 - If the issue is present in the dummy account - then, this appears to be a System Wide issue on the computer.

4 - Download the Application Etrecheck directly from the Developer.

This is a Diagnostic Tool that makes no changes to the computer.

It makes a coherent and readable inventory of both the Hardware and Software used on the computer 

The application is free or paid from added features. 

The Report will Not Reveal Any Personal Information. 

Post back the Full Report - copy and paste - >>>> using the Additional Text Icon ( 3rd Icon to last ) <<<<

Hello kenbedone,

Do you see any kinds of errors or alerts when trying to open Font Book? That can help us determine what's going on. Reinstalling would involve reinstalling the operating system, so that's getting into last resort territory. We would recommend trying what steps you can from If an app on your Mac stops responding, closes unexpectedly, or won’t open - Apple Support for troubleshooting, as well as trying safe mode: How to use safe mode on your Mac - Apple Support That will help us narrow this down further.

Let us know how things go~

Have had good look.

If other Contributor(s) spot something abnormal are welcome to jump in.

See nothing that would cause Font Book to Hang as many times as it has.

Apart from, maybe considering restarting in Recovery Mode

Link below and doing an In-Place re-installation.

This would Install Ventura Over the existing installation and some times will just put things right.

If and only if going that route >>

Do a Time Machine Backup before hand

 2023-01-16 15:30:32 Font Book.app Hang (15 times)

    Executable: /System/Applications/Font Book.app

Welcome 😀.

It would appear there is some piece of Third Party Software Installed and used on the computer.

It is interfering with the Normal operations of the computer 😔

Suggest moving to Step 4 above

Thank you 😀 for the Report.

We will dissect it in detail. 

Will get back to you soon