You won't have to buy a Lucid Air if you want a car with more immersive Dolby Atmos. Mercedes will equip its cars with Atmos audio on all models that use both its latest MBUX interface (introduced with the latest S-Class) and an optional Burmester 3D or 4D sound system. Whether or not you'll driving, you'll hear compatible music in a vertically enhanced sound field — it might not sound like a "live concert" as Mercedes claims, but it should be a step up from the usual stereo playback.
The 4D system includes 31 speakers, six of which create the 3D effect from above. Another four "near-ear" speakers sit in the front seats, and all four seats have two sound transducers (aka exciters) each. Throw in 1750W of total power (including an 18.5-liter subwoofer) and you'll likely be happy regardless of the audio processing.
Just don't plan on buying an Atmos-equipped car right away. The format will first be available in the Mercedes-Maybach in summer 2022, and the S-Class soon after. Other models will follow, but you might not want to count on buying an A-Class with Atmos any time soon.