That's not how this works. The JWST was limited by the size of its faring, but increasing the size of the faring doesn't mean they'd ship a less complex telescope with the same functionality; they'd ship an equally-complex telescope with more functionality. Better for science, yes, but that doesn't translate to more expenditure that could be captured by the launch company. And that still relies on a government that gives a damn about funding science, which is not not the direction that the US is heading in.
That's not how this works. The JWST was limited by the size of its faring, but increasing the size of the faring doesn't mean they'd ship a less complex telescope with the same functionality; they'd ship an equally-complex telescope with more functionality. Better for science, yes, but that doesn't translate to more expenditure that could be captured by the launch company. And that still relies on a government that gives a damn about funding science, which is not not the direction that the US is heading in.