Here's my view: The author of that page has commented here on HN; If my claim was so outrageously wrong as you claim, he would've corrected it.
notice this isn't even a language vs language benchmark. it's libraries and frameworks.
plus I don't think even the author of the julia library in question would agree with your statement: https://discourse.julialang.org/t/the-state-of-dataframes-jl...
as mentioned in that thread, GC and strings, or especially a combination of the two, can be very much a downer in terms of julia performance. That's actually pretty surprising since strings are often as important if not more important than numbers for a lot of data processing needs.
I'd also say in terms of compilation time, some autocaching layer outside of precompilation would do wonders.