I think Mars would be even better then the Atacama Desert for radio astronomy, even at low Martian altitude. We probably won't see MLMA (Mars Large Millimeter Array) in our lifetimes, but if would have extraordinary observing potential!
Atmospheric interference: Water vapor is the worst for millimeter radio astronomy, but carbon dioxide and oxygen also absorb RF at those frequencies. Mars's atmosphere is mostly composed of carbon dioxide, but the average surface pressure is less than one percent of Earth's. Image Credit wikimedia
The Martian atmosphere would be very good for observing since it is a thousand times drier than even the atmosphere in the Atacama Desert. For even less atmospheric interference, we could consider putting out array on the gentle sloped of Olympus Mons, the giant Martian volcano. However, then we would be subject to Orographic clouds in Olympus Mons local weather systems, so perhaps the best location would be in the plains.
Extremely Long Baseline Interferometry:
ALMA fills an important role in radio astronomy not only as a stand-alone array, but as one of many radio-telescopes which can be used in collaboration. As an example, ALMA contributed to the Event Horizon Telescope (EHT) which produces images of a Black Hole (Image Credit: EHT Collaboration):
MLMA could fill a similar role. An important equation in Radio Astronomy determines angular resolution $R$ as a function of observed frequency $\lambda$ and distance between baseline elements $B$ as:
If we used MLMA in concert with ALMA, we would have a ELBI (Extremely Long Baseline Array) with unprecedented angular resolution to distant RF emitters.
Man-made RF Noise: Even though the Atacama Desert is still a relatively quiet RF region, as it is not well developed, there are still a number of interfering frequencies, such as Space-To-Ground Comms, Space-To-Space Comms, and SAR Earth imaging satellites. At least right now, Mars is relatively RF quiet. Hopefully, when frequencies are allocated for use on Mars, radio astronomy frequencies get favorable allocations!