TI still use really outdated hardware (some ARM9 thing) on their high-end nSpire models.
With the same price even HP Prime G2 has way better hardware (NXP iMX6ULL, Cortex-A7, 256MB DDR3, USB EHCI OTG) and wide software spectrum (no Secure Boot enforced.) I've put full scale Linux and Windows ARM (arm32 IoT) on that platform.
Locking out other OSes isn't a main goal of Pluton (although technically it can), there are just too many issues (hey Infineon, Intel and Qualcomm I am looking at you) with existing dTPM and fTPM implementations.
With the same price even HP Prime G2 has way better hardware (NXP iMX6ULL, Cortex-A7, 256MB DDR3, USB EHCI OTG) and wide software spectrum (no Secure Boot enforced.) I've put full scale Linux and Windows ARM (arm32 IoT) on that platform.