What I don't understand is how come all those other current gen games which sold as well as FH3 aren't still in the charts? What happened to all the copies sold between Feb 2017 and now that Mebe is discounting if 2.5m of the MAUs don't count as extra sales?
FH3 has been charting regularly on UK and somewhat US due bundles (nothing wrong, just the reason). It's weekly sales should vary from anywhere less than 10k (costumary for under ~10th) to 15k (like a couple weeks ago where it broke into the top 10 again) It ended 2016 with 400k+ there, and now it could be around 600k. We recently learned that it just passed 200k in Germany, which is the second biggest market for the Xbox in Europe.
Which means that while it's a sought bundle game, it's doing above average in two major markets only.
All in all, it should be around 3mi by now, if not passed that mark.
As I said in my first post, last time Forza/MS talked about (unique!) users, it didn't match sales for that amount of unique users and soon people noticed the numbers matched perfectly with available in-game stats, meaning they weren't unique "unique".
Given that 5mi users would require: the majority of F6 buyers to be different from FH3 (since they should total ~6mi together at best), or FH2-1/F5-1 still have largely active communities, or Forza Apex counting and is really active too, the 5mi users probably overlap between games: That is you are counted twice for still playing Forza 6 and Horizon 3.
What GT6mebe said about using MAU in PR statements instead of sales is sort of true. MS abandoned console sale numbers in favor of MAU statements. It's another way to prop up positive numbers, while avoiding less favorable ones.
But I don't think it's unremarkable at all.
Repeating myself but, even at worst case scenario of huge F6-FH3 overlap, 2-3 million starting your game at least once a month is a great thing.
I think the problem in terms of sales, and it doesn't seem to be a financial one for the studios, is that a game with great reception, good direction and content fails to handily surpass its predecessors.