Transparency is still very expensive unfortunately. DICE spoke about it a GDC talk last year and recommended that the any hit shaders that are used for alpha te

Transparency is still very expensive unfortunately. DICE spoke about it a GDC talk last year and recommended that the any hit shaders that are used for alpha testing (i.e., transparency) should be avoided if possible since they're rather expensive. Their big problems is trees, since leaves modeled as flat squares with their the actual leaf shapes in textures (that are completely transparent around the leaves). "Trees are our biggest problem in ray tracing. No matter what we do they're by far the slowest thing to trace, and they're much worse than on rasterizer, and if you have any ideas of how to ray trace trees efficiently, we're very happy to hear them. We've asked a lot of very smart people and no one has come up with a good answer yet. You can choose between geometry and alpha testing and both are kinda crap." - It Just Works: Ray-Traced Reflections in 'Battlefield V', GDC 2019.