The biggest obstacle to humans staying young until their death through rejuvenation/longevity therapies was the inevitable cancer that would develop because of cells dividing too many times. Now mRNA vaccines and gene editing tools like CRISPR will eradicate all forms of cancer within 10-15 years.

You were born just in time to reverse your biological age to 20 and stay in the prime of your life until you get hit by a bus in your 700's. We made it, bros.