Before XML became a standard and given all its shortcomings, what made XML so popular?

Question

Yes XML is human readable but so is comma delimited text and properties files.

XML is bloated, hard to parse, hard to modify in code, plus a ton of other problems that I

Answer 1

The two main things that made XML widely adopted are "Human readability" and "Sun Microsystem". They were (and there are still) other cross-language, cross-platform data exchange format that are more flexible, more easy to parse, less verbose than XML. Such as ASN.1.