They are just wildly outdated for most tasks. Even projects like frigate suggest buying different hardware. Coral was released in 2019 and hasn't been updated once. With a jetson nano or even a raspi ai hat you get way more tops
Ok I'll clarify: I want to buy a current-ish generation of TPU that can run LLMs. Coral is like 8 years old now
I've been really hoping to get Whisper running on a coral, but it can't even do that. There was recently some progress getting it to export to tflite (and even an official example added) but the coral is missing some instructions.