For example, if a BME280 MEMS sensor is sent 0xd0 as only payload, it will respond by sending back its ... but on microcontrollers, even on the powerful STM32, if i’m doing “bare metal”, ...

STM32 devices come with a variable number of SPI peripherals, ... but many sensors like Bosch’s BME280 and related MEMS sensors also implement an SPI interface in addition to the I2C one.