RE: ETL jobs in Business Central
When it comes to Saleforce in specific it might be worth the time to evaluate some of the solutions that are available for this on AppSource.
appsource.microsoft.com/.../apps
For a more general approach I would say that it depends on what kind of integration platform the other application are providing.
If you can connect to the other application using API's writing AL code for that and run it on a schedule is in general a good approach.
And you have a http client available in AL to do that.
Some applications might also be able to consume the API's that Business Central publish and then that might be a good approach because then the other application can ask for the data when needed instead of having data pushed. That will probably reduce the "stress" on both applications.
If you have a more complex integration landscape maybe you would want to look into using Azure logic apps or Azure integration service.
Using Power Automate is also a popular approach - but i would not recommend that because the Power Automate flows are connected to a specific user and can be difficult to monitor on a solution level.
Please circle back if you need more details around specific aspects of this.