It is there, but for how many more versions?
search for "edit curve" in command finder
"Parameters (legacy)" is what you are looking for
Depending on the spline type selected you get the new or old edit dialog.
It is probably worth looking at the newer curve tools.
Or even better use FIT SPLINE (under fit curve) to create a more smooth relica of the same (associative and you can validate the deviation also simultaneously)