[maxerickson]

Is it robust? I help my mom with genealogy stuff from time to time and the gedcom file we got from some cousins was, let us say, a mess.

I agree it is widely supported.

One thing to watch out for with export is whether you are working with data that doesn't make it into the gedcom file.

[basseq]

As a file format, sure, it's robust. Garbage-in-garbage-out, though. A directory structure would be just as messy, and harder to use.

And great point on export. Assets like pictures are an example: you'd still need to store them somewhere. (IIRC, GEDCOM format points to a file path of some sort.)

Edit: actually, you can embed multimedia (as a BLOB of some sort) directly into a GEDCOM, but I'd leave the files separate to maintain human readability.