Windows 10 Enterprise LTSB 2015 (the original long term support version of Windows 10 Enterprise) doesn't support installing .Net 4.7 at all.

There are an increasing number of applications which require .Net 4.7, we found one early this year.

Promising "10 years of support" for a product is great, but if/when other vendors decide to undercut this, you can still be SoL :(