This subject is not new but annoying, just because it's not corrected since weeks and weeks.
CSV Splits @ Swimming and Running are useless as the entries with every split do not describe the actual split values but just the overall activity results (e.g distance, lap time, avg pace, best pace, avg swolf, etc etc).
The workaround would be copying from the intervals screen, but this is exactly what should not be necessary. That's why you offer a csv output file.
Finally tackle this problem pls.
Best,
- Road.