Tikkun Soferim – Were the Changes Real, and How?

A follow-up asking directly: were the tikkun soferim textual changes real, and if so, how could they be made?

Q. So did they do any changes to the text. (I was just asking if this was real and if it was how can they do it)

According to some (although again, others vehemently oppose this opinion!!) the Anshei Knesset HaGedola made these small necessary changes- see in Hil. Mamrim of the Rambam, where the power of the Sanhedrin is almost unlimited (this is the beauty, “safety” and necessity of how the Oral tradition works and is eternally relevant and Torat Chaim- a Living Torah), but obviously they almost never used this prerogative.