Thank you for your answer.
Nevertheless, few more questions about the limitations. I know, the most correct model serialisation is really challenging problem, but what if we use some tricks?
For example, large variety of models can be described by nn.Sequential with the forward pass looking like this:
def forward(self, x):
    x = self.net.forward(x)
    return x

For these “types” of models all needed source code will be saved. And with other hack like saving the project structure, the model should loads without many problems, is’t it?