The only part of the J&J that is old school is the technology that uses a vector. Adenovirus vectors are not proven vaccine technology. While adenoviral vectors have been tested in far more people than mRNA vaccines, the technology is used in only one commercial vaccine today: a rabies vaccine used to immunize wild animals. So far, no adenoviral vector vaccines have demonstrated they can prevent disease in humans. Beyond that, J&J and Astra Zeneca are still using the same AI designed synthetic genetic protein sequence as the mRNA devices are using - only their delivery system is placing the sequencing into the cell nucleus instead of the cytoplasm. Even though the mRNA shots do not contain parts of aborted fetal cells, these cell lines were most definitely used in their development.