Many black holes have a bright accretion disk outside their event horizon, so visibility for those is not an issue.
But it’s certainly possible to have maximally scary black holes that have no accretion disk and are small enough so as not to cause significant lensing. You could fly your spaceship straight into one of those without even realizing, until you start turning to spaghetti.
> it’s certainly possible to have maximally scary black holes that have no accretion disk and are small enough so as not to cause significant lensing
Now that's a proper cosmic horror.
Supernova and asteroids were always scarier to me because they’re potentially planet-ending scenarios. Whereas a black hole is benign as long as you don’t move into its orbit at too acute an angle.