Nibbles are still a thing in embedded programming and in ultra low bandwidth comms like LoRa. For example you can pack 2 BCD digits into a byte, one for the high nibble and one for the low nibble. This results in the hex representation of the byte actually being directly readable as the two digits, which is convenient.
Datasheet for sensors will sometimes reference nibbles as well, often for status bits on protocols like Onewire where every bit counts. i.e low nibble contains a state value 0-15 and high nibble contains individual alarm flags.