I think that is absolutely a fair criticism. Personally, I rarely run into an issue where I absolutely am bottlenecked by a slow loop. But this sort of thing drew me to Julia in the first place.

There was also an R update in ~2017 that introduced some JIT speed-ups for loops, which made a noticeable difference.

If this is a problem you run into often, I suggest converting your object to a data.table. You can pass a function row-wise over the object very quickly:

https://stackoverflow.com/questions/25431307/r-data-table-ap...