This has been solved in v3.8.

You mean that this ticket is a "feature request", OK.

But (to me) the missing feature looks like a bug in the implementation of the CSV export feature :-)

Not a bug but a feature.

CSV export is an important feature to analyze data in other tools (be it text-based tools like diff, or a simple spreadsheet). Yet CSV export is not working satisfactorily on all hierarchical views (which is most views for accounts, taxes, etc.) because it will only export top-level entries and there is no way to export all childrens.

In some case this can be worked around by using the sub-view that offers a flat view of the same objects, but there are two problems here: not all objects have a flat view (for instance account templates do not have such a view) and some of those flat views voluntarily filter out childrens (that seems to be the case for taxes).

Please consider modifying the logic to export all children by default.