That inadvertent confirmation of iOS 13.3's imminent release was on the mark. Apple has released the new software (plus iPadOS 13.3), whose centerpiece is an improvement to Screen Time parental controls. You can set limits on who your kids can call, text or FaceTime, including managing contacts and setting time-specific limits. If you don't want your kids starting video chats with friends after 9PM, for instance, you can. This won't help if your kids use third-party apps, but it's a start.
There are also some bread-and-butter functional improvements. You can create new videos when trimming clips in Photos, and Apple News has fresh layouts for News+ stories from papers like the Wall Street Journal. It's easier to like or dislike stories as well. And if you're security-conscious, you'll be happy to know that you can plug in a FIDO2 security key instead of typing in a password. Add to this the usual round of bug fixes (including one that prevents Mail messages from downloading) and this is a worthwhile update, even if parental controls don't matter.
There's also a tvOS 13.3 update, although it's not nearly as substantial. The biggest improvement is an ability to revert the Apple TV's top shelf to show your Up Next queue. And did we mention a minor watchOS 6.1.1 update? It's clear that you'll have a lot of updating to do if you expect to stay current in Apple's universe -- let's just hope Apple can afford to slow down its rapid-fire update releases in 2020.