Is it:
a) someone with an undergraduate/graduate/doctorate degree in CS with specialization in AI/ML?
b) someone with a non-CS degree (Math/EE/CE/Other) who specialized in AI/ML?
c) someone who attended an AI/ML course on Coursera?
d) other?
If they previously integrated Nuance's speech recognition into a product, they were just an engineer, now they are an AI engineer. Worked on mapping product which does routing before? Well route searching is an "AI" kind of problem so they are an "AI engineer" too, and so on.
AI/ML is the new "big data" basically. As soon as "big data" appeared, nobody was doing just "data", they were all of the sudden doing "big data".