Ventura 13.3.1 wrecks Final Cut Pro — any hope out there?

I just updated to Ventura 13.3.1 and... Final Cut Pro now won't open.

FCP gets stuck "validating" Audio Units.

So I uninstall the Ads and... FCP just finds another AU to get stuck on.

Note: I was using FCP earlier today without incident.

Note: The "offending" AUs have been working just fine for months if not years.

And the most awful part: I remove "everything" associated with an "offending AU" and... FCP still thinks it's "there"!

Delete preferences. Restart. Do anything and everything you can think of and... FCP is stuck "validating" something that's just not there.

This update has wrecked my work as I can't even get to FCP projects I started a few hours ago.

I trust Apple is updating to provide us with better security.

I wish Apple would do its homework re. unintended consequences before issuing the update.

This really, really sucks.