Given enough money, a JIT can be made arbitrarily fast, it seems (e.g. - JVM, LLVM bitcode interpreter)
Given time, don't assume any particular language implementation will always be faster. Go might only run faster than Javascript on the odd years, depending on corporate budgets for compiler / VM tuning the previous year.
The JVM has received a lot of money and attention over the years, yet still falls quite short of its direct compiled competitors in almost any benchmark. The threshold for "enough" when it comes to improving a JIT is still arbitrarily high.
Given time, don't assume any particular language implementation will always be faster. Go might only run faster than Javascript on the odd years, depending on corporate budgets for compiler / VM tuning the previous year.