“Done properly from the beginning” means explaining why a particular feature is either included or not. In this sense, Go is done properly from the beginning. It would be wrong to add every popular feature uncritically.
"They are likely the two most difficult parts of any design for parametric polymorphism. In retrospect, we were biased too much by experience with C++ without concepts and Java generics. We would have been well-served to spend more time with CLU and C++ concepts earlier."
It is sufficient to actually care about history of programming languages design, acknowledge the paths trailed before since FORTRAN came up in 1958, no need for omnisciency.
