I think that taking the plan with a grain of salt is rather healthy, as we know many others that underestimated the hurdles of making colour film, even coming from B&W.
What I want to point out is this sentence in their blog post : "The Film Project will utilize our newly developed proprietary machine and emulsion process, allowing us to be self-sufficient in our production."
It seems that they indeed weren't capable of producing film up to recently, and are just starting with what's the easiest, black and white film. However, they apparently already managed to have T-grain film, even showing examples of the structure, and a film example. I'd say it's rather transparent.
One thing I'd like to add is the industrial strength of China nowadays, if there is one place where a completely new manufacturer can emerge it is China, with experienced engineers, low manufacturing costs, and many brilliant minds.
With Fujifilm's history, we know that some new manufacturers can enter fast, with sufficient investments. I'm fairly confident that they could manage to make colour film in the coming years.
However, their roadmap seems a bit optimistic, but to be fair they didn't include a timeline. if we can see colour film made next year or even in 2 or 3 years, it would be quite a feat. Peel apart, I'd guess is many years away. But I'd like to be shown otherwise !