Update on this situation.
Since my previous post I've experienced a similar problem on two consecutive days while playing RR3 update 13.0.3, happening yesterday 21 and today 22 November 2024.
In both cases I was playing the Red Inferno event and had closed the game, to reload it shortly after. It gets stuck during loading at the blue R3 Real Racing screen. After a while the system shows a message saying: "Real Racing 3 is not responding. Do you want to close it?".
Same as in the case of my previous post, clearing the cache, restarting the device and then reloading the game do not solve the problem. Clearing game data in the app settings does, but that requires a reinstall afterwards. After reinstalling, restoring the saved game will once again cause it to crash and not finish loading.
Here's an odd detail: once this problem occurs on my main device (smartphone), the game will also fail to load on my backup device (old wifi tablet), even though it had not been in use and RR3 was not active during the preceding hours.
The only way I have been able to bypass the problem last night, was by deleting game data on both devices, reinstall, decline the Profile Restore and then log out of my account on both devices. Then use the 2nd device to restore the "unlinked" cloud save, then login and run a race to upload that profile so it can be downloaded on my phone (This didn't work on the main device because the linked and unlinked saves are identical there).
Right now, it appears that even that elaborate procedure doesn't work anymore. As soon as I've restored a saved profile, it proceeds to download some race assets which crash the whole thing again. And there is no option to decline that download: tapping the close button in the upper right part of that screen has no effect.
With this in mind, I now believe that this is a bug in the latest release.