Thanks for this, the whole tuning and upgrade side of it had somehow slipped my mind. Forza Horizon is an open world driving sim. It's not quite as heavy on the sim side of things as Forza Motorsport, but it's actually pretty close. The fact it's jam packed with non-track racing activities doesn't really change that.
Ultimately, it kind of feels like the arcade racer is almost dead at this point, at least until you go to the complete extremes with Mario Kart. As much as OnRush was obviously doomed for a dozen reasons, no-one seems to know how to succeed in this sub-genre any more. The worst thing is that while I think back on various arcade racing games I've really liked over the past decade or so (Burnout Paradise, GRID, Blur, Motorstorm) I'm not sure a new version of those would actually find success. It feels like it should be kinda easy, especially given the lack of competition, but game after game is falling flat right now.
No worries, and apologies if I sound condescending at all! I have a fairly specific, staunch view on what defines an arcade racer and I generally get fired up about it even when it's not warranted.
If I can put it another way, an arcade game gives people the same limited choices so then when someone wins/beats a time or whatever then it's purely down to skill. PGR and DC had that because you could always pick a car and a track and the rest is skill. But with something like FH, there are so many variables, even when the racing is on a fairly defined circuit. I believe there were modes where you couldn't use tuned cars or you're given fixed parameters (like they donate the car to you or something) and that's closer to it, but that's only ever a small part of the game.
In that sense, I guess that's why arcade racers are failing: Big drawcards are customising the hell out of cars, collecting as many as possible and be given freedom and variety. When you don't have those things and focus more on refining skills, to outsiders that just looks like there's fuck-all content and a waste of money (look at the complaints for DC and PGR not having a big enough car selection compared to Forza/GT).
And to bring it back, I think that perception of lack of content (despite there being a dopamine-overloaded sense of replayability when actually playing it) is what worked against Onrush and specifically how much it cost. Why would I pay ~$90AUD for some arcade game that I've never heard of when I can spend the same amount to get an officially licensed Formula 1 game with all the teams and drivers I'm familiar with, along with all the tracks? It should've launched in the same range as Rocket League or Wipeout Omega. And considering it was developed in two years I think Codemasters were fucking crazy charging full retail.
/rant