At the end of the day, people wanting the definition for “the set” to be this or that just comes down to how difficult/easy that makes it for them to pursue the set so that they can feel accomplished in having completed it. What if it doesn’t really matter whether you have the full set or not?
If I was gonna write a book about PS4 or Vita games, I would include every single game that was ever made for the US market.. yes even the ones that we only ever found 5 copies of. If it’s worth being mentioned in the book, then to me its part of the set. Full set collecting is a thing of the past, but people don’t want to accept this reality. So instead of accepting it, they want to change the definition.