Beyond consulting companies, there's also just so much back office / line of business software out there - procurement, human resources, payroll, enterprise performance management, etc. Most of it at high level is slow and onerous because it needs to be reliable and predictable. It cannot fail fast and stakeholders place premium on the feeling of certainty / forecasting.

I understand that, but didn't agile arise because that feeling of certainty/forecasting proved false? That is, experience showed that the end result ran over budget, underdelivered or simply wasn't needed anymore by the time it was done?

It's not that Agile is chaotic because it's cool, it simply (allegedly) surfaces the chaos and uncertainty that was already there. And in my limited experience in consulting, I did build one of these heavily specified LOB software that got canceled near finishing, with all of us laid off and all the effort wasted. This was some CRUD system for an insurance company, by the way; "boring" software by definition.

(To be clear: I'm not arguing Agile truly fixed this, just that what was before had serious enough problems to spark a paradigm change).