The PCA9554 library is pretty solid for the Arduino consumers. It definitely works with not just the ESP32 architecture - but I've also tried it on the RP2040's. I can't see why it would be incompatible with any of the SAM or AVR architectures - since the library depends on the twowire library for the heavy lifting.
With the architecture=esp32 ---- the library shows up as incompatible for all but the esp32 devices.
I think it would be a great update to simply update the architecture property.