Higher antibody levels and more antibody targets aren't the same thing.
The mRNA vaccines cause one protein from the virus to be present, so you get antibodies against that specific protein. More traditional vaccines use dead/weakened virus, which will trigger production of antibodies against multiple parts of the virus.
This is not necessarily true. It depends. People in my family who took the vaccine and had visible side efects (headaches, fever) for a day or two have more antibodies than other acquaintances who got hospitalized with the disease.