A couple of years ago, Apple introduced the T2 chip. It combined several formerly separate controllers, refining operations and increasing security. Check out what it does for us and our Macs here: Apple’s New T2 Chip Explained: What does it do?.
Here’s what Apple Support has to say: About the Apple T2 Security Chip.
The video is from November, 2018, but it sums things nicely.
It’s Leonard’s fault!