It's a perfectly reasonable choice: flexible, well specified, well supported, reasonably performant. I think the extreme level of hype 20 years ago was overdone and (just like with anything) there's good ways to adopt it and bad ways. But as a basic technology choice, it's fine. Particularly these days when you can have a coding agent write the parser boilerplate, etc. for you.

XML is much better than JSON for document-oriented data like messaging and web pages. Use the right tool for the job.