One of the problems would be acquiring said corpus. NN corporations got away with scraping all human made content for free (arguably stealing it all), but no on

One of the problems would be acquiring said corpus. NN corporations got away with scraping all human made content for free (arguably stealing it all), but no one can really prove that their specific content was taken without asking, so no lawsuits. NYT tried but that was workaround and I don't know the status of that case. But if NN corpo will come out with explicitly saying that "here, we are using a Nature journal dump from 2024" then Nature journal will come to them and say "oh, really?".