We use SSIS to copy production data to Reporting Repositories. We use it for data movement from and to SQL or flat files such as CSV or fixed data. This is primarily to build and update a data lake and data warehouse.
More custom use cases are to do DQ validation comparing source to destination, and to extract data from bat files and SSIS files in order to build a metadata repository for documenting and mapping all the ETL packages. We use this to find the packages responsible for any particular table or file, or vice versa. This system, along with statistics logging, also gives us summary reporting capability.
I like that SSIS lets us build programs top-down. Starting with the control section, then drilling into the details of the steps make more sense than what Informatica requires, where you have to build each block first, then use a different tool to build the control structure.
In production, SSIS does a very good job of distributing work to many threads. It is robust and does a good job of handling overload conditions. It is simple for basic jobs, yet able to do very complex tasks. When all else fails, code can be written to make your own custom task or even tool.
I believe SSIS is not given the credit it deserves. SSIS does what most other new vendors tout as great features. But it is a very mature and stable product, unlike those others. It is supported by a larger company than many of those other products.
The error messages are pretty clear and point you to the problem well.
I am disappointed that Azure Data Factory did not stay closer to SSIS.