It's the most viable at the lowest price point I believe. Other companies like Ericsson can also provide 5G but I think Huawei is furthest ahead yes. This has really been poor planning on the part of the UK government going back a few years - this decision has been coming for a long time but not enough effort seems to have gone into creating a better set of choices. Instead we are accepting Huawei despite believing they are a bad actor and only now starting to seriously plan for reducing our dependence on them.