you should really give it another try, using a current version. all of your five points applied at some (very early) points in Jami's history, but assuming they reflect its current status is just spreading FUD. it's no different from insisting that computers are giant, slow, building-sized pieces of equipment that nobody could carry around.

FWIW, I have zero direct experience with its mobile apps, I don't even carry a tracking device. I find the Qt-based app on GNU/Linux-libre pretty decent, though I'm not so fond of GUIs that attempt to emulate attention-grabbing anti-patterns.