And yes, TI calculators have indeed been improving, apparently.
The TI-84 Plus is a graphing calculator made by Texas Instruments which was released in early 2004. There is no original TI-84, only the TI-84 Plus, the TI-84 Plus Silver Edition models, and the TI-84 Plus CE. The TI-84 Plus is an enhanced version of the TI-83 Plus. The key-by-key correspondence is relatively the same, but the TI-84 features improved hardware. The archive (ROM) is about 3 times as large, and the CPU is about 2.5 times as fast (over the TI-83 and TI-83 Plus)[citation needed]. A USB port and built-in clock functionality were also added. The USB port on the TI-84 Plus series is USB On-The-Go compliant, similar to the next generation TI-Nspire calculator, which supports connecting to USB based data collection devices and probes, and supports device to device transfers over USB rather than over the serial link port.
Because that would have eaten into their price gouging. In the age of the iPhone, Texas Instruments was able to charge upwards of $100 for a Zilog Z80 powered nothing machine because they’re quasi mandatory for high school and college students.
I bought my TI 36X Pro at $20.
I paid over $100 for my TI-84 in like 2012 almost 40 years after this basic ass hardware was created.
I figured out you could emulated the TI-84 plus on a smartphone for free, around 2012. I just used that for my college math class, but it probably would’ve been harder to get away with in a high school class.