The original author of Jupyter is Fernando Pérez who is a proponent of Fortran and has always supported LFortran as well as our wider efforts at fortran-lang, see for example his recent tweet:
The original author of Python is Guido van Rossum who is also a supporter of Fortran, as evidenced by his recent tweet:
So we have the support of all the important people that we need and the door is open for Fortran. The rest is on us to walk through the open door. We have to do the work, and that is exactly what we are doing.