It's a much less mature engineering field than any of the others, so it's still a lot of R&D to get anything done. PhD is a big help in teaching you to do that

It's a much less mature engineering field than any of the others, so it's still a lot of R&D to get anything done. PhD is a big help in teaching you to do that well. I still recommend it, though at some point in the future it won't be necessary.