The Foundation Models paper is a strategic attempt of the Stanford AI researchers to coopt the field and define a research program for large-scale pre-trained models. Propagating a new term that is slightly hyperbolic is one way to differentiate your work from other's. But it's only marketing.
Watch how all Stanford-adjacent research will now cite the Foundation Models paper instead of the original BERT paper, other surveys of pre-training, or field-specific papers. There are over a 100 authors on that manuscript, it's a cheap and easy way to increase their researcher impact.
Other researchers naturally aren't too happy with this cheap marketing approach.