Does the game have alternative damage models?

The current damage model is very forgiving (I haven't noticed difference in handling with the exception of when having a flat tire) and allows crashing at extreme speeds (to the game's credit, falling off a clip in Monaco and Greece wrecks your vehicle). Is it possible to disable damage altogether or use a more realistic model, for example?

From Steam Forums, it does not seem possible to disable damage. You can read for yourself since its rather to the point, but basically the user asked if you can disable it, to which someone replied "nope," and a bunch of others seem to agree and point out various examples of why you can't.

If you are on PC, it looks like you can try this mod (disclaimer: "online events are disabled while the mod is installed") for more realistic damage. But other than that, it does not appear that you can alter it in any way.

There is no way to disable damage all together. Even for the sake of wanting to practice more tracks without having a damaged car, you aren't realistically practicing then.

There is a steam discussion where someone was asking something pretty similar.