I can definitely appreciate what you’re saying, and I’ve experienced the same frustration myself. That being said, I’m amazed they’ve even found a way to support foliage at all. Dynamic geometry is challenging to support in GI, as is transparency and masking, and especially deformation. Foliage is all of those things, in addition to being dense and a poor self-occluder, essentially the most challenging phenomenon lumen could possibly handle.
And even then, we’re getting support for improved transmission and GI in lumen. I’ve tested out experimental builds of the engine with the new features, and they look absurdly good for being in real-time. Depending on your settings you might get a little ghosting, a little noise, but by and large the final image holds up. I can’t argue that foliage isn’t a massive headache, but with what lumen can do now, the possibilities are just incredible.