I actually disagree with the whole "Project Blue Beam" script. If real aliens did make contact with humans, world governments would likely be instantly hostile to them (although hostile in a diplomatic sense, not 'immediately fire missiles'; although we could have an accidental hostile incident of course) for the simple reason that the elites do not like the idea of their power questioned, undermined, or second to anything. It is the libertarians on both sides of the political aisle that would be friendly to alien contact, both for philosophical wisdom ("ALIEN SAID THEY DON'T USE GAS POWERED SHIPS AND HAVE NO GENDERS, EVERYONE LISTEN TO THEM!") and for profit ("Dude, they use thorium reactors. We could build our own in, like, ten years"). But the authoritarian left and right? Absolutely not, they have everything to lose from real alien contact.
And as for fake alien contact, most of the population simply would not go along with it without serious proof. Lights in the sky would have dazzled earlier generations, but the current population is very cynical of anything to do with authority. It'd take aliens coming down to their town and ordering the local cuisine for them to believe in their good intentions. Think about it, you can't even get rural populations to like [insert ethnic minority here], what makes you think they'll like aliens telling them what to do?
The much better script is this pandemic "Build Back Better" script. Masking authoritarianism in the guise of health, environmentalism, and racial redistribution is easier to implement simply because you can demonize anyone who disagrees.