RNG???
Apparently, the suggestion of making all tour reward cars available to buy or rent in Free Play is currently the most voted idea in the Forza forums, following the addressing of the largest complaint at the time, which was the car progression system.
*Please delete if this is a duplicate topic/idea With the rise of so-called “exclusive reward cars” for Forza Motorsport, what worries me is that they’re not available as rental cars in Free Play, and that their respective tours and even the showcase event will eventually expire, which could...
forums.forza.net
They could really make it in a way where if you complete the featured and Open Series tour, you get the car in question for free, but you'll have to buy it if you choose not to play through them. Even then, you'll still need to grind a bit to buy them. That way, no car gets left behind. But then again, you can
rent them in Free Play if you want to jump right into the action.
Having all tours permanently added to the main Builders' Cup experience would also go hand-in-hand as well, considering how barebones the career mode actually is. Making them permanent will make the game more user-friendly and will increase the replay value.
These come-and-go mechanics seriously need to stop in FM8 as soon as Update 8, or eventually. Turn Ten just needs to address this and reassure us that they'll do something to make these cars available to buy or rent in Free Play, and perhaps make all tours permanent.
This has absolutely nothing to do with Game Pass, and it's a tactic just to get people to panic-play. They can remove these mechanics to actually improve sales of the game and increase player count.