Question About Windows Server 2019 Minimum FFL

Hello,

I'm looking over the documentation for the Active Directory functional levels and I'm confused about the minimum functional level requirement for Windows Server 2019.  In the Windows Server 2019 section, it says that the minimum level for 2019 domain controllers is Windows Server 2008R2.  But in the Windows Server 2008 section, it says it supports Windows Server 2019 domain controllers.  Am I reading this wrong?

This is the resource I'm using:

https://docs.microsoft.com/en-us/windows-server/identity/ad-ds/active-directory-functional-levels

Thank you.