It's literally designed as the opposite of that at every step. Probably because Forza Horizon fills that role nowadays.
This iteration is but FM historically hasn't been like that.
Like i've said previously, I love the new Forza because I spend all my time in the multiplayer but from
MidGenRefresh wants it has shifted significantly. Sure FH does all those things but that's way more of a casual game too which I play but strangely hate the multiplayer and just like to explore and take photos.
If you want to collect cars then the new FM is worse because cars are not given out like candy anymore and you have to really think about the cars that you want to spend your hard earned credits on.
If you want a single player campaign then the new FM is worse than even Forza 5 that was very barebones as it was anyway. You are very limited with the events that you can enter by two factors, one is that you don't have a lot of choices due to the majority of events being locked behind a few and you have to work through them to unlock the next. The other is around the first point, you need to buy a suitable car for every event which you may not have the credits to buy.
If you want freedom to modify and tune your cars then the new FM is worse than all previous FM games because you don't have access to the parts until you level up the car you want to put those parts on and each level it drip feeds you those parts. This is one aspect that I personally am not a fan of because I like to download other peoples tunes, I have a few favourite tuners and I tend to download theirs and apply them to my cars because they are better at it than I am and no matter how much I tinker I never get them as nice. The problem is that all those tunes are locked until you level up the car enough to unlock all the parts that the tune uses. This arbitrary requirement to fully level a car before you can have the freedom to apply any community made tunes you want is going to really hurt the people who love to share their tunes and is a really stupid and clumsy game design choice for people who want to create their own tunes. I've been playing a couple of days now and my highest level car is about 35 (max is 50). By that metric it's going to take me another play session to get it to max. Another knock on effect of this system is that the new community made tunes appearing on the database are generally not going to be making use of all the available parts meaning that the quality of available tunes is going to be worse than previous games. There is no way to tell what level the car was at for the tunes you are looking at on the database and all you get is a padlock icon to say you can't have it! For me personally this whole system is more of an annoyance than anything else and i'll just slap a hodge podge of parts together to get it to the required rating for the class until it's fully levelled and I can then download my favourite tunes. Due to this system though I will probably favour the fixed spec races so I know that everyone is in a similar car and i'm not going to be hampered by driving a car that isn't level 50 and decently tuned compared to the rest.
All that been said, I do still really think that this is my favourite Forza yet with the penalty system and the tyre and fuel choices being a breath of fresh air. The tyre wear model is really REALLY good for a console game and you can really feel the grip fading along with the lap times until you pit and get fresh rubber. This means that anything over about 4 or 5 laps is going to require a fuel and tyre strategy. Do you go with the hard tyre and fuel for the full race, do you go with a soft first and a tiny amount of fuel and pit early, do you go medium tyre first and then switch to a soft in the last couple of laps or do you pit mid way through and stick to a medium tyre throughout, the options are vast. The tyre and fuel model is so well implemented and I think they really nailed it straight off the bat. I have had quite a few races where the pit strategy has made a huge difference to my overall position. One race (7 laps) I didn't have a qualifying time (due to joining just before race start) so I decided i was going to pit early (lap 3) and fuelled very light with soft tyres. This meant i could push through the field hard at the start when the pack was bunched up and did my early pit stop. When I emerged from the pit stop I had quite a lot of clear space in front to push into on a medium tyre. When the rest of the drivers pitted towards the end of the race I made up loads of positions without having to overtake on the track and finished within the top 10. It wasn't the podium finish that was always the be all end all aim in previous FM games but, it was a really nicely executed pit strategy that came off perfectly and the satisfaction of getting that right felt amazing. I rarely win online races as i'm not good enough to put down blistering lap times so spend most of my races in the middle of the pack, in previous FM games there would be some prick who would intentionally put you off the track and I would end up in the bottom half of the table at the end of the race and the entire pack would be really spread out with the leaders lapping the back markers every race. With the new penalty system however that has reduced significantly and there is a lot more wheel to wheel racing with a proper tight chasing pack than ever before in a Forza game. Even at the end of the race there is a tight pack more often than not and rarely so far have I seen anyone intentionally putting people out of the race. Cheating by cutting corners is now gone as well and the races now feel like real life races where the drivers are properly staying within the track an avoiding collisions where possible. There are many issues with the game but I am more than happy to overlook those issues because the good stuff that is there is very very good!