In PlanetaryProjectDefs.xml per project there are line like that:
<ManufacturingPerBonus>10</ManufacturingPerBonus>
<BonusMax>1</BonusMax>
What does that mean exactly? I would suspect that means that principally one gets the bonus defined in the project for every 10 manufacturing points, but since BonusMax = 1 every manufacturing point over 10 doesn't have an effect.
That seems to be what I observed until now, seeing the projects having mostly only a very small effect. But I now have begun a new game (with a Steam Workshop faction) and I actually can see a difference according to manufacturing the planet produces as if BonusMax was not factored in in my above assumption. Has there something changed in the game of late?