Most people want more life. For most people it's also the most terrifying part of "the natural human experience".

If you're happy to die, why be bothered by others' trying to live longer? You won't be around. And assuming people can finance it themselves, is it really a problem for society?

There are cultures where dying isn't feared like it is in Christian based societies. It's considered a natural progression and part of nature.

I'd also say people may want more life for themselves, but what does that mean at scale, forever?

Because living longer is a huge drain on resources that could be better spent on other things. End of life care is expensive and rarely results in a "good" life for the the life being extended.

I assume you mean that dying is the most terrifying pat of the natural human experience. Also, I'm not sure why you infer that me thinking death is a natural part of life, means that I'm happy or eager to die.

There are many reasons that people living forever would be a problem for society, the most obvious being an ever-increasing population.