It was growing at a surprising rate (+44% last year, vs. -11.5% from Apple or -5% from Samsung), about to overtake Apple as the second smartphone manufacturer in the global market. That's kinda huge. And that was just in smartphones. It was also doing
much better than all the rest of competitors in network equipment, with most of european operators planning to use Huawei for their 5G deployment. And they were also booming in laptops (the Matebook X Pro is the best high end ultrabook in the market... and they just entered the laptop market a couple of years ago), etc.
Also, don't forget they are
spending a lot in R&D. More than Apple and approaching Microsoft and Alphabet. If you think they are just another average chinese smartphone manufacturer you are very wrong.
They have Qualcomm powered devices, but they are moving away from them to a full in-house Kirin lineup. They are also pressing TSMC to build exclusive fabs for Huawei in mainland China. Concerned enough yet? Well, the US government obviously is. They don't want another tech giant capable of rising even above Samsung, and coming from a country they don't trust. So... they are just trying to kill it or control it.