I don't know either what they meant, but for comparison NumWorks calculators are clocked at 216 MHz (100 MHz for the older models, and 550 MHz for some of the latest ones, but not everywhere), so it doesn't look that much out of the ordinary, maybe a little underpowered from my experience with the first NumWorks but eh idk it's a calculator and unlike the first NumWorks they don't try to do CAS.
Thanks for clarifying. I think this is an ARM and a break from a history of Z80 and Z80 adjacent CPUs. I do get the impression TI have done a good (financial) job milking these products whilst under investing in real product innovation.