Post Scarcity Cthulhu: the post-scarcity galactic civilization is happy to share their technology with us. And it’s very, very alien, mostly organic.
e.g.: You can access the Galactic Information Network, but the implant most compatible with humans looks like a giant scarab beetle that covers the top of your head (it replaces the top of your skull). Exposure to alien thoughtforms makes you somewhere from openly weird to a raving loony.
Just as there as Assholes Who Don't Get It among humans, there are Assholes Who Don't Get It among the galactics. They're the antagonists. They mostly don't engage in exponential expansion, but they have terrible habits like denying the free will of other intelligent species: eating them, puppeting them, enslaving them. Because eating cloned tissue and puppeting shells and being served by subsentient AIs just isn't the same as the good old days when a byakhee was a real byakhee.
Humans, of course, can cause cognitive dissonance among aliens just like the aliens do among humans. A loud Hawaiian shirt tends to freak out predator species that rely on stealth and camouflage, for instance. Rigid endoskeletons are icky to tentacled beings with hydrostatic skeletons.