Al / ML / Data Science people – what is your preferred title?

I've come across a plethora of titles across industries, including:

- AI researcher

- AI engineer

- Data scientist

- Machine learning engineer

There are slight and subtle differences in the implied roles but I've also seen these roles used interchangeably.

Is there a "best" role title that is most sought after? And what does the role progression look like? For example, for MLE I would assume:

- Jr Machine Learning Engineer

- Machine Learning Engineer

- Sr Machine Learning Engineer

- Team Lead - Machine Learning