No, I'm Not saying don't buy Huawei's stuff because it's insecure, or has back doors or any of the security concerns *Alleged* by the US gov. The problem, which you may not have heard about, is that the US gov may follow through in its attempts to kill Huawei. If they're successful, any warranties or support would go away, which is why the warning. Needless to say such a move could potentially wreak havoc on telecommunications in the EU, where Huawei's stuff is commonly used, at the least raising costs & thus prices.
Or it may just go away, as it did with the US gov's feud with ZTE.
Part of it's politics, pure & simple... The admin's gone after foreign automakers too, though only verbally so far, despite the fact that the gov's own stats show auto companies like Honda use more US-sourced parts than supposedly true blue companies like GM. Part of it's no doubt pressure from Huawei's competition. Huawei doesn't have a presence in the US like it does in the UK for example, so there's no one to speak in its favor, or perhaps more importantly in the US, make political campaign contributions.
At any rate, while they've been given a *temporary* 90 day reprieve, companies like Google, ARM, even the organization behind the SD & micro SD formats, are forbidden to do any business with Huawei.