I wouldn't be surprised if the 5% drop in "Data Scientists" is from the same role being up-branded as something like "AI/ML Engineer".
I typically go with whichever likely matches the most LinkedIn search filters of the day. Unfortunately, I can’t bring myself to put “AI” in my job title (despite the potential career benefits) because it just feels kind of icky. Maybe for a role that performs fundamental AGI research, but that’s about it.