The 24MHz clock on the core is modest by today's MCU standards, but it is enough for the class of low-power sensor and control tasks this part targets. At this speed, the core can handle real-time sampling from the 10-bit ADC at reasonable rates, run a simple control loop, and manage I²C or SPI communication without breaking a sweat.
FRAM — the real differentiator
The 8KB of FRAM is what sets this apart from the sea of Flash-based MCUs. FRAM writes at bus speed — no page erase, no write-before-erase cycle — and it is non-volatile with endurance many orders of magnitude beyond Flash.