I've added a new app to the list of apps to handle a given URL scheme and I got the alert box saying the handler for that URL scheme was successfully changed. The list looks a bit awkward, adding it here for completeness:

However, opening a URL with the given scheme from Terminal does not use the newly set default app.

I'm not sure if that's a bug due to the UI glitch or is the preference pane just not working on Ventura?