Capacity/Production numbers are usually a drop in the ocean. For 30 to... 200 on a bad day influence, you can have a new planet, which within 10 years an edict lasts will be populated enough, depending how fast pops migrate, breed and stuff get upgraded, I guess at worst, you'd have a planet that does about 40-60% of the original. We and got stuff like planet size, and surrounding resources too, adding up to that. It's 40-60% of everything, not just the minerals or the energy or the science.
Compare to burning 150 for an edict and getting 20% more in just one department. They're clearly the last option if you got no choice. It costs you less minerals but it's temporary, won't snowball you, and certainly worthless in early game.
Even if such edicts gave boosts of 50 to 100% it would not break the game, and would do a small empire a lot of favor, while to a very large one with many planets, it'd be a negligible drop in the ocean, and having many planets would still be the way to go.