Generally speaking, neither of these websites or their profiles/trees should be considered more accurate than the other. Any accuracy depends on the source records available onsite and/or attached to their profiles/trees.
For the referenced individual, the Geni profile does not appear to have any source records attached, while the FamilySearch profile has several source records, with images, attached.
If I were researching Pieter, I would use the FamilySearch profile and records as my starting point.
edit: FamilySearch profile is conflated. Records for Petrus belong to a different person. I will make corrections.
WikiTree profile Gouws-582 appears to represent Petrus.
edit 2: I've updated Pieter's FamilySearch profile to include his parents, baptism, spouse, and marriage records, as well as his death data from his gravestone image.
Pieter's new profile is G5NP-3PL .
I haven't reviewed Pieter's siblings and children yet, but the records for Petrus indicate he was not married.
I will post again if I find any more adjustments are needed.