Abandoning Earth and our bodies
To truly live "forever" will require us to completely remove these
biological shells we are currently encased in. Otherwise, while we
might add a century or two to our current life space, we will merely
be delaying what happens to us when we get old anyway.
I can also envision the rich and powerful - and now immortal -
escaping Earth and abandoning it to the rest of humanity, who
will be stuck on a once beautiful world slowly decaying.
We should only become immortal if we have a better reason for it
than we are afraid of death.