Yes but maybe in hundreds of years they could prevent senescence and death. Just because we can't live forever that doesn't mean we shouldn't tell the younger generations to shoot for the stars.
There's no *ultimate* meaning which is a good thing because it means you can always continue the journey and look for something new.
Impossible, there are an infinite amount of problems which means there's an infinite amount of fun to be had in solving them.
You're talking about invincibility and not immortality. An immortal couldn't live in a capsule unless it constantly fed in some kind of energy source that is needed to keep your brain running. It would also need to be based on the consent of the person inside.