Does anybody know how much an ML model is actually worth to build a new model? Like when they start making a new model, do they modify the old or do they start from scratch?

I'm asking to know how much owning a model is actually worth, not in how much it could make money by selling use, but in how much it deprecates and keeps value to make a new one. If say one side of China/US lacks out on a model generation, do they only need to follow progress on the science behind it and when they own the data, the algorithm and the hardware all they need is "just" time and energy or is it important, that they actually have their on instance of a large model from every generation continuously?