Currently, materials project does not compute phonon frequencies. Since it requires creation of larger supercell (if done through the finite difference method) or through DFPT which is very expensive, such calculations are not done in materials project.
However, pymatgen can be used to perform the phonon calculations using tools like phonopy (Refer to mapidoc for further information). But these calculations need to be done in a local machine and not on the computational resources at materials project.
"Can they be made available?"
--> Not possible at present. Maybe future versions might have this features.