The United States has many negative things about it, and its democracy is flawed at best, but you don't get combo points for tacking on adjectives. It is plain by reading the dictionary that the US is not totalitarian.
"Successfully" is the real loaded term here. Those that claim to see the cabal behind the curtain unfortunately have woefully underdeveloped facts to support it.
A subverted liberal democracy secretly run by a cabal of oligarchs but on the surface still playing hands-off with everyday people's lives is not totalitarianism. Totalitarianism is not some generic insult to describe any oligarchy or authoritarian government. Totalitarianism is the extreme absence of individual liberty.
For instance, the US has been doing down on the Economist Democracy Index in recent years. "Flawed democracy" is not totalitarian, but it's trending away from "full democracy" and cries of totalitarianism may well be responding to real concerns.
In the abstract, I wonder if it's better to raise such issues with incremental language and small arguments, or to raise them with hyperbolic claims, or to tailor to your audience, or some other combination.
You don't have to tell me that I'm weird, I already know.. Most people seem to think dictionaries are obsolete because spellcheck exists, not caring that the primary purpose of dictionaries is to look up the established meanings of words. I know I'm weird for thinking these established meanings should at least be acknowledged when deciding to stray from them. If people want to use hyperbole to make a point I think that's fine, and know that even if I didn't think it was fine it wouldn't matter because I couldn't stop them. But my personality is such that when I see somebody doing it without acknowledging the established meaning of the word, I feel compelled to remark on it. Particularly when people are doing it with serious words with heavy connotations, like totalitarianism or genocide.
As for the deteriorating state of American democracy, I share most of your concerns, but I don't see a trend to totalitarianism specifically. For instance the government now exercises less control over who people marry today than it did a generation ago, much less three or four generations ago. I do perceive disturbing trends in corruption, wealth distribution, and administrative competence. But a corrupt incompetent oligarchy is not synonymous with totalitarianism.