It's generally not maximizing lifespan people are interested in but rather maximizing health span which is the period of time you are healthy and able to operate at a high level. If done correctly you die with minimum time spent disabled.

If you max health span, you're going to live longer.

If you die, you're probably not healthy to begin with, or you die to very sudden trauma.

any brain disease that makes you mentally unhealthy but lets your body survive comes to mind

It's not only "living longer" as a whole organism, but also your individual organs living longer (that ultimately impact aging). Take ovaries for example: Menopause causes major health problems (osteoporosis, cardiovascular disease, etc) for women and women now spend on average more time post-menopause than pre. There's a good writeup about this problem and the companies researching it here: https://spannr.com/articles/oviva-therapeutics-raises-11-5m-...

that's a nice catch, thanks!

If I could have a thousand years to read and study deeply and just write and think, I would take it.

Yes my loved ones will die and that will make me sad. I'll grieve and move on. My life is not theirs - their death does not mean an end to what I am doing.

Flip the problem. If you could bestow a friend/family member with a thousand years, even knowing you will die, would you?

One of the ancient greek prophets declared the apocalypse would happen in 9 generations. She was quite wrong. Most doomsday prophets are (well, probably all but the last one).

This isn't just about extending how long you live but also the reduction of disease. That's something that seems highly promising about some of these treatments

Curiosity? See where this ride is going and maybe have some hand however small to steer it?

More time to do the things you enjoy.

More time to be a productive member of society, you mean.

Average life expectancy in the US is 78, with some states seeing average age around 74.

Do you want to live no longer than average, so lets call it no older than 75?

Who wouldn’t want to be healthier than average at a given age?

It's funny to me that there is always someone that predictably asks this question because they can only imagine living longer while being unhealthy.

"a reason to stay alive while people I love are dying"

I'd like to be healthy enough to help them when they are dying.

Because I'm so "so smart, intelligent and clever" and the alternative is unknown to me. Simple 1+1

Exactly!

The people you love can take it too?