The vast majority of black holes do NOT have an accretion disc

The video game Elite: Dangerous depicts the Milky Way galaxy, including the numerous black holes that are known to exist there. If you go to such a black hole, it will be essentially invisible, the only way that it exhibits itself is by how it distorts the background (ie. gravitational lensing.)

Many people believe this to be unrealistic because they have this misconception, no doubt spread most prominently by movies like Interstellar, that all black holes have a very prominent bright accretion disc around them. In fact, when mentioning black holes, most people probably envision the image of the black hole in Interstellar in their minds.

In fact, there are some YouTube videos that take footage from Elite: Dangerous depicting a black hole and adding an accretion disc in post-processing, and the comment section of such videos will invariably be full of people commenting on how much more realistic it looks and wishing that the game implemented that kind of visuals.

The problem? The way that the game depicts stellar-mass black holes is actually realistic!

The fact is that stellar-mass black holes do not have any sort of visible accretion disc. They are too small for that. They are, indeed, pretty much like the game depicts them: Completely invisible, them being "visible" only in how they distort the background. There's nothing visible orbiting them.

If a stellar-mass black hole has a very closeby normal star, gas from the star may be falling into the black hole in a spiral pattern forming a sort of accretion disc, but even then it would be extremely faint, probably too faint to be seen by eye.

Only supermassive black holes in the centers of galaxies (and a few other places) may have a prominent visible accretion disc. And even with those it's theorized that not all of them might have one (for example, it's currently unknown if Sagittarius A*, the supermassive black hole in the center of our Milky Way galaxy, has a visible accretion disc. It's not a given that it has one.)

In other words, the depiction of the black hole in the movie Interstellar is not unrealistic either, but that's because it's a supermassive black hole, not a stellar-mass one.