With this integration into Marriott's booking engine, citizenM will now reach a whole new, more mature audience that may not expect pod-sized rooms, especially at the average rate citizenM commands. Sure, they may have stayed in a Moxy and already got annoyed with the "check in at the bar" concept, but even Moxy still doesn't have wall-to-wall beds. Also, Marriott's booking engine notoriously buries room sizes from display, something citizenM's engine never did.
I guess the reviews that will come in during the next summer's points redemption period will be interesting.