Agree. To add on, don't do any side work if that is not your main job role.
The following is an example for data analytics/science that applies to other areas: There is an agencywide drive to train more staff in data analytics/science from the academy side. Going for the training is fine, but I would not recommend anyone do any side data analytics/science work, *especially* if in a non-technical dept (e.g. business dept like policy/regulation).
The reasons are simple:
1. You will be rewarded - with more work.
MAS does not appreciate technical work, as with most government agencies apart from maybe GovTech. You will only end up being the "go-to person" in office for all sorts of data analytics/science work, while your colleagues who refuse to learn (especially the senior ones) simply assign their work to you and coast by (with higher pay even, for the senior ones). There is no return once you are viewed as the "go-to person" in the dept; if you refuse work now, you run the risk of being marked down as uncooperative. Management is also complicit: I have heard staff who literally went to management claiming they don't know how to do data analytics, and management simply assigned the work to someone else who knew how to do it (instead of asking the staff to learn on the job).
2. You will not be recognised. There is no formal HR recognition process in place for side jobs like this through higher base pay, CEPs and performance grades. The higher CEPs and performance grades will go to your colleagues who *present* your data insights at management forums, but woe betide you if something is wrong with these insights, since you will get all the blame for actually *doing* the work. Maybe HR will do something about this, but I don't have high hopes. Even if HR comes up with some formal recognition process, it will probably be implemented in the next decade or so, going by HR's usual leisurely timelines that lag the reality of the job market by years.
TLDR: Don't do any side work if that is not your main job role. Learn what you can, and start job hunting once people start approaching you as the "go-to person" in office.