Horror that relies on the monster aspect to induce fear, especially visual mediums where you sometimes have to give comprehensible forms to things that are supposed to be incomprehensible (and therefore derive most of their power from the reader's imagination), misses the point. I suspect that's a big part of why you're so tired of it—a lot of horror misses the point.
Good cosmic/lovecraftian horror is ultimately about total alienation, othering, and loneliness, which are feelings that are universally upsetting to social animals. The Thing, for example, has a creature that's viscerally upsetting, but the fear comes almost entirely from the looming sense of dread, isolation, and futility. An unimaginably bad thing is happening, it's up to our hero to stop the almost certainly unstoppable, and he can't even identify the threat he's supposed to overcome. Even if none of the humans around him are infected, he is, for all intents and purposes, totally and utterly alone. It's the ultimate anxiety.
Intellectually understanding a concept doesn't make you immune to the emotions that come with that concept. We all need different things to trigger these very basic fears, and maybe most cosmic horror doesn't flip your switch, but knowing you're gonna die one day doesn't mean your final moments are going to be to totally chill.
