I2C is a wonderful interface. With four wires and only two GPIOs, you can connect a whole lot of sensors and devices – in parallel, at that! You will see I2C used basically everywhere, in every phone, ...
The I2C/I3C bus is the backbone of out-of-band communication for DDR5 modules. At high speeds, even minor disruptions can lead to costly troubleshooting and delays in bringing new products to market.