For additional information:
In the Microsoft Update Catalogue, KB4495588 for Server 2008 R2 SP2 covers .NET versions 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, and 4.7.2
The fixlet title in bigfix only mentions .NET 4.6 and 4.6.1
This appears to have something to do with relevance 6. Not all of the releases are accounted for here.