* 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. ^[citation^ ^needed]^

...are we accidentally going to open a portal to hell by trying to get doom running on something it shouldn't? Is that how it finally happens?

That would be the Ultimate Doom. Real Doom too.

If it can run on a microwave why wouldn't it run in a fancy future computer?

(Yes I know it's more complicated than that)