In a manner of speaking, yes. However, for a matured black hole, the interior spacetime is empty except for the singularity, so there is no real 'density' of matter inside the event horizon. If we take the mass that goes into a black hole and divide by the spherical volume of the event horizon, we end up with an effective density for the matter inside the black hole which can be used by outside observers to estimate the tidal forces produced by the black hole. You can do this yourself, given that for every increment of 1 solar mass, the event horizon radius increases by 2.7 kilometers. You then see that low-mass black holes have very high densities and therefore very strong tidal gravitational fields compared to supermassive black holes. In the latter case, the tidal field is so weak that you might not realize you have entered a supermassive black hole until it was too late for you to turn around and head back out.

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