i can only speak for myself but imo it´s easy:
i want the italian league to do well and become better because in the end this will benefit juve as well BUT RIGHT NOW i want juve to grow as fast as possible and i´m convinced that the additional money we would gain from a roma cl exit (in case we qualify) would help us much more than a "strong serie a". furthermore, i want the chances for another juve scudetto to be as high as possible and i think roma would suffer more from playing tons of EL matches than (probably) only 2 more cl matches.