If you updated to macOS Ventura and Wallet & Apple Pay do not work, here is the fix. The error is: Apple Pay is disabled on this Mac because security updates are not automatically installed.
This is an odd bug that some Apple Mac users have found after they updated the operating system to macOS Ventura. For some strange reason, the Mac thinks that security updates are disabled, and perhaps missing, so for security reasons, it disables Wallet & Apple Pay.
Apple Pay is disabled

You cannot add debit or credit cards to it and if you try, you get another error message like this.

This is very strange, especially when all security updates are installed and automatic updates are enabled. However, there is an easy fix that will put things right.
Have you checked Wallet & Apple Pay in System Settings on your Mac since you upgraded to macOS Ventura? Is it OK or does it need fixing? Here is the fix.
Toggle update settings off and on
Software Update has moved in the new macOS Ventura System Settings app. It used to have its own entry in previous versions of macOS, but like iOS and iPadOS, it can now be found in the General section.

Select the General category in the System Settings sidebar and then click Software Update on the right.

Even though Automatic updates is set to On, and updates are downloading and installing OK, there is actually a problem and Wallet & Apple Pay do not recognize this. Click the i button at the right side of Automatic updates.

Whatever the state of the switches, and mine were all turned on as they should be, turn them all off and then click the Done button.
Return to these settings, turn all the switches back on, and then click the Done button again.
Apple Pay fixed
Now when you return to Wallet & Apple Pay in System Settings, everything is OK. The error message has gone and you can now click Add card to add a new debit or credit card.

What a weird bug in macOS! This error may be fixed in a future update to macOS, so the problem outlined here may only be temporary. Still, it is useful to remember the old tech support fix for almost everything: Turn it off, wait a few seconds, and then turn it back on again. You would be surprised how many things it fixes!