This is an illusion. Reports first extract and calculate various data from the database. Then, they format it according to hard-coded instructions, taking into account parameters (like date ranges, descriptions, etc.) you might have added (depending on the report). It is merely coincidence that data used for some reports, like the Balance Sheet, happens to look formatted. It is not. For other reports, different data is extracted and used. Sometimes, the coding extracts information on nil-balance accounts or transactions because that is part of the process necessary to have all needed data available for formatting. The final formatting is what sometimes excludes nil lines.
Regardless of what data the program extracts and uses, it will be shown in an export. As you have seen, the result is that some exports look more like the final, formatted version of a report than others.
Sorry you feel that way. I’m not the developer. I’m a forum moderator, a user just like you, trying to help others understand the program.