It just prolongs the inevitable. If the average life expectancy is 70 years or 200, it still doesn't matter much in regards to things left undone; on your death bed, you'll still regret not loving your children more, not having the courage to ask her out, not traveling, not working on your ideas, etc... Consider that some opportunities only happen once, and then pfff, they are gone forever. Most of use are full of regrets until the end, and growing organs in labs is only a small comfort.

The other dream of course is for us to become immortal, but that's magnitudes harder than growing a liver in a laboratory, not to mention that even if possible it would open up a huge can of worms in society, problems that are even harder to overcome than technical issues.

Also, for all the advancements medicine appears to have, remember that we aren't even able to cure cancer and HIV, we aren't able to cure Alzheimer, we are only able to keep asthmatics under control and my child's doctors weren't even able to tell me the reason for why my child had the Lyell's syndrome a month ago (thankfully he's fine now, but it did freak us out).

We aren't even able to solve the problem of freaking bacteria becoming more and more resistant to antibiotics, and should I mention we aren't even able to find a cure for the flu or for common cold?

So don't kid yourself. You are going to die, you probably won't get past 90 years and your children, your grand-children and everybody you know will die too.