Reset button schematic for ATTiny84

Yes, that's the point, a low level causes a reset. The voltage specs are worst case. At worst, the chip will consider anything below 0.2Vcc to be a low level, and anything above 0.9Vcc to be a high level. Pushing the button forces the reset pin to 0V. When the button is not pushed, the reset pin will be held at Vcc by the resistor.