"If all life is sacred, as some people believe, then by that same token, aren't all deaths equal?"

It would be hard to find ethicists in any culture, at any time, that would find those "tokens" equal. I don't think it's a stretch to say that every culture has allowed as how killing in self defense is allowable. Therefore, with just that exception alone, no. all deaths are not equal.

It is the assumption that those who believe life is "sacred" and those who believe "well, it's all we got" have a common interest in determining, for their community good, how to judge our place in the commission, or hastening, or lengthening of that inevitability we all accept, "death".