I read an interesting article in Xbox magazine or some magazine back when Halo 5 was coming out and it was an interview with Kiki Wolfkill I believe, or maybe Bonnie Ross.
Don't quote me! Anyways when asked what the purpose of the subtitle "Guardians" was used for they went on to explain that Halo "wasn't Final Fantasy" and that in some way they probably will move away from the numbered games.
Should Halo 6 be the first Master Chief centered title to stray away from a definitive number or should it be "Halo 6" all the way?
I didn't find the right solution from the Internet.