I have the same issue, after upgrading to iOS 13.5.1 the rear camera on my XR will not focus on objects more than ~12 inches away from the lens. The twitter thread below is what happened when I contacted Apple about it. I wouldn't expect them to acknowledge the issue, looks like we'll just have to wait for them to quietly fix it (if they ever do). Having been an iPhone user since the iPhone 3G and having had Apple break multiple functionalities on my device over the years (just discovered through the Apple support process that I can't even open a .ICS file on my iPhone unless it's through the built-in Mail app, what's up with that?), this is the last straw for me and I'll be looking into migrating to another smartphone platform after my XR is past its useful life.
https://twitter.com/thisisp5ych0t1c/status/1279473489875857409