To explain the joke:

!Half of the early FF games weren’t released in the West until later on. FF1 was, but 2 and 3 were not. So when 4 released outside of Japan, publishers thought it would be weird to have the numbering go from 1 to 4, so 4 released internationally as FF2. And then 5 got skipped over as well, so when 6 released internationally, it was released as FF3. However, they wanted to standardize the numbering starting with FF7, because FF7 was a Big Deal™, so for players outside of Japan, the series numbering suddenly jumped from FF3 to FF7. And the skipped games were later released internationally, so the numbering is now consistent with the initial Western numbering now largely forgotten.!<