I started using Julia in December, DataFrames are in a sort of weird place because they're so much less necessary compared to e.g. Python. In Julia, you could just use a dict of arrays and get most of the benefits, thanks to libraries like Query.jl and Tables.jl. Thus the ecosystem is a lot more spread out. I actually use DataFrames much less than I used to in Python.
This is mostly good, because you can apply the same operations on DataFrames, Streams, Time Series data, Differential Equations Results, etc., but it does mean that some of the specialized optimizations haven't made it into DataFrames.jl