The history of everything in biology is us looking at a plant and going “oh wow, it’s green, that means it’s only absorbing magenta!” and then finding out years later that the plant is almost entirely green except that every hundredth cloroplast is actually magenta and that’s the signal the plant uses to tell when the sun is up which is how it times its seed releases, which is why our crops all died this year and won’t grow back.
Sorry, but that's not how it works. Energy is energy, and we can measure what's reflected. Chloroplasts _themselves_ are green, btw. That's where their name comes from.
Why plants are green is a mystery. There is no accepted explanation. A compelling theory is that during the first ocean oxidation event, dissolved iron started crashing out as iron oxide, which strongly absorbs the green light.
I sure hope you’re right.