Its a cause of death. We like to avoid those. And we know multicellular organisms exist that can maintain their telomeres and avoid senescence.

We are almost certainly going to be able to genetically engineer that into future people at some point, among a lot of other useful things. Dunno if we are going to manage to get gene therapy that can alter living humans so drastically before they die, though. And who knows when it will happen, just that it almost certainly will, unless we blow ourselves up.