This just isn't an area we need to optimize. The relationship between pollinators and angiosperms is working, as long as it keeps going we don't really need to worry about how energy efficient it is. The pollinators aren't going to exhaust the inputs to photosynthesis by drinking too much nectar. The real problem is that flying insect biomass is declining rapidly.

I'd wager satisficing is better in the context of ecosystems then optimizing, to keep the system flexible and robust to change.

it’s even more efficient for the bees who effortlessly and by their very nature produce enough that an invader can eat and be satisfied and yet still leave them with plenty! a veritable honey pot