We have some D415s and the depth image quality drops drastically under florescent lights. It's easy enough to fix by placing IR filters over each of the stereo sensors. For now, we are just buying some IR filter sheets and cutting holes where the filtering isn't needed.
Does Intel have any attachments, or plans to include hardware filtering like this in a new model?
Depth images being negatively affected by florescent lights is a known problem. Some users have found that the negative effects can be reduced if they run the streams at an FPS that is close to the frequency of their particular lights. For some people it has been 30 FPS, and for others it has been 60 FPS.
I do not know of plans to incorporate a hardware fix for the issue. However, in the latest 5.10.6 firmware Intel introduced a fix for flickering when auto-exposure mode is on, so it may be worth trying that firmware to see if it improves your results.