I'm not Christian, but I think that any argument which takes the concept of the Antichrist seriously but removes it from the context of Christianity has no merit.

The Antichrist only makes sense within the framework of Christian eschatology. Invoking the archetype but reframing it as a secular political and cultural force that opposes AI and technological progress seems like meaningless sophistry meant to grant some greater profound scope to what is in essence just basic anti-leftist, pro accelerationist rhetoric, but which only works with a facile understanding of what the Antichrist is supposed to represent, which is opposition to Christ.

And in that sense, Peter Thiel and Donald Trump fit the criteria far more than, say, Greta Thunberg.

Exactly which is why the argument has no merit.

And even if it was in context to Christianity it has no veracity as the entire argument stands on faith which is fallible.

Well said. The Antichrist becomes, in Francis Schaeffer's term, a "contentless label". It becomes just something that the speaker thinks is bad. But people (even non-Christians) still have some memory of it meaning something, so it's still an effective term for "something bad".

By the way, "Jesus" also has the same issue. That name is used at times to support positions that are explicitly contrary to what Jesus taught.