From Wikipedia : extract, transform, load (ETL) is a three-phase process where data is extracted, transformed (cleaned, sanitized, scrubbed) and loaded into an output data container. The data can be collated from one or more sources and it can also be output to one or more destinations.
Reverse is only meaningful when you're used to a specific view that ETL can only load into a single destination. (Usually data warehouse)
Just like the term "push notification" which are a specific kind of communication from the server to a mobile device but in fine, it's the device calling a service to know if there are any notification waiting for them.
A Message Queue in other words...
You have been downvoted for this but you are entirely correct.
The differentiation in terminology is entirely a fiction created by marketing teams for these kinds of tools.
I'm saying this is someone that sees the benefit in this specific tool and desires to implement it for my team.
There is no reason that tools like FiveTran couldn't handle the same things that tools like Census do. They just focused on a specific set of use cases, ignored other ones that were more of a paradigm shift. Then when teams created products that fill this void they referred to them as reverse ETL for entirely marketing reasons.
It's an example of where enterprise software gatekeepers such as Gartner drive negative value by deliberately confusing the language to sell their magic quadrant reports to risk adverse executives at massive corporations.
Reverse is only meaningful when you're used to a specific view that ETL can only load into a single destination. (Usually data warehouse)
Just like the term "push notification" which are a specific kind of communication from the server to a mobile device but in fine, it's the device calling a service to know if there are any notification waiting for them. A Message Queue in other words...