What is this "rest"? Are you really convinced this is a correct generalization? What about Mi 5, Mi Mix, 4C/A/X, can you show what they copied? Their first well-known phones barely had any design to speak of, and the same could be said for modern Redmi Notes etc.

Loose sim cards, really? I've had experience with 6 Xiaomi phones to date and never noticed that. Shaky GPS? Yes, this happened on one bottom-line Redmi, but it's hardly pervasive as far as I can tell. Software is debatable – it's not Pixel experience, I'll concede, but also definitely not TouchWiz. Battery is on average better than for most Chinese brands or for Apple, though inferior to, say, LG and Samsung. (One actual issue: camera performance is varying, typically it's bad without customization).

I won't argue that at least some models are clearly very closely copying a major brand (for instance, MiA1 is openly compared to iPhone, Mi Note 2 has Samsung S6 design), but this does not appear to be a crucial part of their business strategy (unlike the more abstract "Chinese Apple/cheap Samsung" sales pitch), and comments like yours strike me as repating a vague stereotype. In the post-iPhone era, striking design originality is rare to find, and Xiaomi doesn't seem more prone to copying than most others. They jump on the bandwagon as soon as the new technology becomes available/popular, and that's about it.

Please compare the highest end Xiaomi phone with an iPhone. Not their low cost phones

But it's the low cost ones that have contributed to the "rise" of xiaomi referenced in TFA. The high cost ones nobody is buying.