* Rather, a program superficially imitating the first level of Doom is able to run on a simulator of a quantum computer.
Not to diminish this accomplishment, but based on the level geometry on display there this is obviously a bespoke but very basic 3D-ish engine, extremely simplified, built from the ground up to do this and is not an actual source port of Doom before anybody gets too excited.
While it's amusing I don't think it really serves to illustrate too well the actual exciting parts of what quantum computing is actually theoretically capable of. Regular old boring Turing-compatible binary computers are already perfectly capable of running Doom already. [citationneeded]