Really I guess I don't know what that is then as I buy the Teensy since it has so much IO, multiple UART, multiple I2C busses, sd card reading, etc...
edit: interesting
(Teensy | Pico)
Special Features: CAN Bus (3x), SDIO, S/PDIF | PIO (Programmable I/O) (8 SMs)
The Pico PIO has an instruction set and can be programmed.
You write PIO assembly that runs autonomously on a state machine, with explicit timing (e.g., out, in, set, mov, jmp, wait) and cycle‑accurate interfaces. The CPU communicates via small FIFOs, and interrupts are optional; the PIO can be “fire‑and‑forget” for many protocols.