The name is still kind of ugly. Maybe something like Move to Nodes (description: Move inputs and outputs set in the modifier to a new node group) or what Simon suggested.
Seems like you could move the - 1 into range(...).
Make sure vscode removes trailing spaces automatically.
Better use two separate functions that call a common function instead of adding optional parameters to this one.
Avoid using input as variable name because this is a built-in function in Python.
Something is wrong here, there is no return value?
This tag is wrong. Changing socket availability does not add/remove sockets. And if you say that making a socket available is adding the socket, then making it unavailable would also delete it.
This is problematic, because the tree might be visible in multiple node editors, all of which would have to be updated.
I think this could be implemented more efficiently (e.g. by storing something on bNodeSocketRuntime, or by only keeping track of the old node index which might work because the sockets of a node are consecutive in all_sockets()).