It was both, and part of the reason platforms pulled support is that keeping up with XMPP was bad ROI. You're Facebook. You want to provide an instant messenge

It was both, and part of the reason platforms pulled support is that keeping up with XMPP was bad ROI. You're Facebook. You want to provide an instant messenger you can iterate on quickly. You can put the work into making it XMPP-shaped and working with the community (whatever they means... Are you going to slip ship targets because Pidgin doesn't work as a client for your implementation?). Or you can just write and ship your own service and client at your own pace and not care about any other developer's needs or wants because you're trying to serve Facebook users, not developers.