Imo these are researchers. Their job was to validate their algorithm for doing generative super-resolution on a dataset, they chose the largest and most well-known dataset, it worked reasonably well on their dataset. The model itself is not productive ready for at least the reason that the dataset is not representative. This is ubiquitous in ML papers, they validate their idea on not completely realistic but widely available datasets. The outcome is a piece of knowledge about the behavior on that dataset not a product.