I noticed that System.ValueTuple.dll is appearing in the build folder now.

It seems to be listed as a dependency:
https://github.com/swharden/ScottPlot/search?q=ValueTuple&unscoped_q=ValueTuple

but I don't think any code is actually using this...

The new lines came in with this commit: 23c1794