Yes, the inverted cross has it’s origins in the St. Peters cross, a symbol of humility, due to St. Peter feeling unworthy to be crucified in the same manner as Jesus Christ. But get this - it has been appropriated by some Satanists as a symbol of opposition. While it’s not an actual symbol adopted by LaVeyan Satanism, it has been & indeed is used in this manner for almost as long as Satanism has been a thing. Satanists aren’t that fucking stupid, the ‘St. Peters Cross’ argument isn’t a new one. This is not the only symbol that has been appropriated in this manner in history, & there isn’t always one, single definition & interpretation of any one symbol.