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

One of the major advantages it has over things like CSV files is that it can represent hierarchical data easily. To do this you either need a self-describing tree structure like XML, or a pre-defined format such as SWIFT or EDI (and if you've ever dealt with either of those, then you'll realise that XML is trivial to parse in comparison).

One of the reasons it's actually quite easy to parse is because it's 'bloated'. Those end tags mean that you can accurately match the end of elements to the start and work out when the tree has become unbalanced. You can't do that in the 'lightweight' alternatives such as JSON.

Another reason it's easy to parse is because it has had full support for Unicode encodings from the start, so you don't have to worry about what the default code page is on the target system, or how to encode multi-byte characters, because that information is all contained within the document.

And let's not forget about the other artefacts that came with it like the defined description and validation mechanism (XSD) and the powerful and declarative transformation mechanism (XSLT).