Re: Won't work in the UK...
To a degree that's true - but I'd expect that to be true in any country. Certainly, in an office with a fair percent of tekkies, there's one or two with showcase mobiles (e.g. iPhone X), but there's a fair mix of older models and "second-tier" brands - LG, etc. One person is even actively waiting for the OnePlus 6 launch tomorrow.
Personally, I think the biggest issue is that they're coming into a mature market where there's very little (from a consumer perspective) functional differences between manufacturers or models: barring brand-name bragging rights, pretty much the only two differentiators are "iOS or Android" and whatever camera-enhancement gimmick has been bolted on.
Then too, the second-hand market is flooded with older handsets which are more than fit for purpose - e.g. you can pick up a 2-year old Samsung S7 for around £200 if you shop around, and it's still a competitive all-rounder.
So good luck to Huawei - I think they're going to need it!