ActiveX is from. 1996, and java applets are from 95. I'm not sure if those technologies were capable of much back then, but the web used to be a much more diverse place before traditional plugins got purged and replaced by Javascript; I'd argue that javascript would be the worst way to do any kind of interactive website back in those days, because almost everyone was on Windows and the alternatives were so much more useful.

XMLHttpRequest was part of a COM component (or maybe its own?) and was therefore able to be embedded in any Visual Basic program or Access or FoxPro front end. To be able to make calls to the internet invisibly, without a web browser? In one of those classic 90s Windows UIs? It looked and felt like magic.

The browser isn’t the only consumer of an api, they are called server to server as well (and this was particularly common when they couldn’t be called directly from the browser). Headlines from other sites, weather, hit counters, all that great late 90s web innovation.