There is no way it implements the entire RV32I base profile. Maybe it only implements the instructions that are relevant for CS students taking a computer architecture class. That is typically what these breadboard CPUs implement.
RV32I is pretty tiny. Particularly when you can squint hard enough at the spec. FENCE can be a nop. EBREAK and ECALL can be something like a halt of the machine.
Arguably, RV32I is "only the instructions that are relevant for CS students taking a computer architecture class", judging by the history in its earliest published spec [0].
