The game is reviewing very well. Positives way more than negative stuff to say.

Nope. See Forza 5.

But Forza 5 still scored well in spite of glarring issues.

Forza 5 was a good foundation, so I knew it was a safe bet Forza 6 would review considerably better.

Arguably one of the best racing games this generation

I really worry about the franchise personally, high praise aside, beyond adding long overdue weather effects and handling, and some new cars, it just feels like an updated forza 5 to me.
Feels as though they are hitting a platau in terms of ideas, and horizon is the overflow for that.
What i'd like to see is a wider range of disciplines, touring cars, dakar, etc.
Wish both Forza and GT teams would stop focusing so hard on making the cars as accurately modelled as possible and spend that time making the game itself more diverse, and work harder on customization options, better decal editors (image import, anyone?), maybe even a body kid modeller for more advanced users.

Frankly it feels more like Forza 6 and GT6 are paid service packs to the previous titles.

Again, they score well but I find the direction they focus their efforts on disappointing.

Brash Games - 9 - "For fans of racing sims and/or of the Forza series, the streamlined career mode and the improved handling make the game an essential purchase."

New York Daily News - 4/5 - "A quality racer, a game that dares to think a bit outside the racing sim box but still delivers plenty of classic Forza fun...Forza Motorsport 6 is an easy title to recommend to the racing fan and the casual gamer alike. It’s a racer with something for everyone."

I guess forza is the fifa of racing games.   At least F horizons is a spin off from the series.