One problem I see with your actual message is that the narrative being consistently pushed is that this is really just some moral duty the US is carrying out. "Ban such a device from a dictatorship so that the free countries have a chance". Which, if you lived long enough, you must have heard being repeated ad-nauseam every time some country was in need of some "democracy". Hindsight shows us they were all left out worse than they were.
But worse than that, even if the problem was unfolding for decades, every time there was such an intervention it just so happened that it was just at the right time when the US needed it. And it just so happened that it benefited the US and US companies the most. Or exclusively. Like leaving the US again holding a monopoly on data gathering in the world, or excluding the main competitor in mobile and 5G from the US and even world markets.
So it's easy to wonder and ask the question: if it's a moral duty why wait so long? Was it for a cheaper iPhone? Why invoke reasons that were there for so long exactly when China starts to become a concrete threat on the super-power stage?
Look at it from another perspective. In light of the NSA revelations, and knowing the vast quantities of data Facebook or Google are collecting and sharing with the US government (for some morally dubious outcomes for the society) which are highly incompatible with the European values and ideals of rights and freedom, would you support an initiative where all these big-tech companies would have their EU operations be moved entirely under a European company?