T@B were once pneumatic as well Tanky, very few GA aircraft having electrics in the 50s, 60s, powered by a venturi stuck out in the breeze.
The T@B has its uses over and above an AH. Clem Atkins at the RVAC in the 60s used to teach spin recovery under the hood in Chipmunks using the T@B, the AH would have toppled during the gyrations, so of no use. Do people practice partial panel these days?