Well, this is a primarily user-driven forum, with casual ST presence; and ST usually does not discuss their design decisions here.
Sigma-delta demodulation can be performed in software, as done in various PDM-to-PCM libraries; although it takes up some portion of the processor time of course. Maybe the FMAC could be employed for this partially in 'G4?
Dear @Fanuc30 ,
Thank you for the question. As a general rule, the definition of a new MCU is a business, application and solution driven , where we try serve General purpose applications on different market segments for STM32 excluding automotive. We are creating several series for some common applications with a specific flavors, for instance L4 series are battery operating or Ultra Low Power applications where each 1uA or even 1nA counts on applications budget, the natural continuity of L4 can be either L4+ , L5 and our Recent STM32U5 series with new security standard on top of ULP . G4 series is addressing another market application which is Mixed signals and Motor control applications - Analog integration, and real time control . Here is below a global view of the series .