It is nourishment. You will get hungry again and you will want to eat a full, well-balanced meal. Gongyo is a good meal. Young people today want everything to come out of a microwave oven. You want to go blip-blip and have a turkey dinner in two seconds.
Good things take time.
As for gongyo being invented by corrupt priests, that is the talk of no respect. Gongyo was established at Taiseki-ji, which is now the head temple of Nichiren Shoshu. For hundreds of years, priests would go to places on the temple grounds and recite parts of the sutra. That is how we got five prayers in the morning and three prayers in the evening. Whether we like it or not, Soka Gakkai tradition has roots in Nichiren Shoshu tradition.