You are right. I did install Rosetta for sure and have the same files as you mentioned. I did the installation through custom install enabling Rosetta manually in the installer and did not lose anything, as expected.
That's what I was thinking of doing, but I was scared off by the fact that the Custom version also showed "Essential System Software" with a check mark that I could not uncheck. I was concerned that installing those files might erase the whole volume and I didn't want that to happen. Thanks for the info. It may come in handy again sometime.
