I think the point he tried to make was that if only "hello world" produces a 1.3 megabytes executable, the file size of a fairly complicated program made in Go will be significantly larger than the same program implemented in another language.
Anyway it can be improved, but to me there are far more important things to be improved about Go than the binary size of small programs.
% du -k eval/eval
2040 eval/eval
% strip eval/eval
% du -k eval/eval
1864 eval/eval
Don't just assume. Measure.It's a tradeoff, and worth it in my opinion.