I would go further and say that the modeling isn't even a big deal (in terms of state machine complexity) as long as you are enforcing immutability at your domain boundary. If only domain methods are able to mutate state, it's a lot easier to find where bugs might be hiding. If any consumer of your domain model can mutate anything in any way it sees fit and then invoke some generic UpdateState(model) method, then you have a much bigger problem.
Put differently, as long as you have good accountability of all the things that can change the state and are comfortable with how that set of things operates, then you are probably in a decent position.
That's fair, and is similar to what I would've written if I'd elaborated more on my "poorly managed state" comment. If you apply good modular/OO principles you at least constrain where state is managed in a way that makes writing, maintaining, and testing your system more tenable without an explicit model.
Put differently, as long as you have good accountability of all the things that can change the state and are comfortable with how that set of things operates, then you are probably in a decent position.