But can't you see the difference here? There is no argument that dumping mercury in a river is good for society, the environment or anything else. It's only "good" for this companies profits and even the real value there is a question given the impact on most people working there.

But extending human life? Maybe it will be bad. Maybe people will keep having children at the same rate and with no one dying anymore the whole planet is completely full of selfish people who don't care about others of the environment. Maybe only the rich will have access, block everyone else from getting it and control the world by simply out living anyone who is in their way.

But what comparable things do we actually see in history? In every country I'm aware of, once basic survival is taken mostly for granted people stop having kids as quickly and often as they can. In fact these days people often wait so long they depend on science to make birth even possible in their advanced age. And most people have, at most, 2 kids.

Imagine if we lived 10k years. Some people might say "well, lets have our kids right now so we can give up 18 years or so now and then have the rest to ourselves" but I suspect most people would say "what's the rush?". Some would even say "why invest 18+ years to extend my legacy to someone I can't control, can only marginally influence for a decade or two? In 10k years they're bound to solve death all-togher. I'll be my own legacy! And if, after 9,900 years they still haven't done it, I can always reproduce then". Imagine not wondering if there was a Troy, we could just ask the people who lived there. In society, we tend to be safe from some tragedy until most people who lived it are dead then we fall in the same trap again. What if they didn't die?

I say all that to say, it is not remotely obvious that extending human life is in the same category of behavior as dumping mercury in the river to make a few bucks so the consequences should not be the same or even similar.