The closest analogy is specific tech skills, like say DBs, for a small firm its just something one backend dude knows decently, at a large firm there are several DBAs and they help teams tackle complex DB questions. Same with say Search, first Solr and nowadays Elastic.
Yeah I mean I guess we’re saying the same thing then :)
I don’t think prompt engineering could be somebody’s only job, just a skill they bring to the job, like the examples you give. In those cases, they’d still need to be a good DBA, or whatever the specific role is. They’re a DBA who knows prompt engineering, etc.