>But you do operate on a larger stage and sticking your head in the sand and pretending the rest of the world doesn't exist is also not going to work.
I'm sure that's how tobacco and oil executives justify their paycheck: "If I wasn't doing it, someone else would". Probably lots of criminals justify their crimes using similar reasoning too.
Ultimately it's not quite true. If you quit your job at that tobacco or oil company, it's going to take a while to find them a replacement for you. That replacement might not be quite as good at the job (why were you picked for the job in the first place? Probably because you were the strongest candidate.) You aren't going to totally halt EvilCorp by quitting, but you're going to give it a speed bump.
In the case of OpenAI, we have to consider what organization is likely to replace them if they throw in the towel. If it's a more cautious org like Anthropic, OpenAI throwing in the towel could actually be a good thing from the point of view of their charter: https://openai.com/charter
