Hell, I type this, and I fall for it too: I'd much rather be able to live forever, without fear of Alzheimer's or a failing body. I have no idea how I'd pay for that, but I'd be a liar if I said I didn't want to Not Die.
Such as what exactly? No-one knows - including you - because no-one has ever run old "software" on young/rejuvenated "hardware". I think that 99% of people in failing hardware given the option to try their 18- or even 30-year old bodies again would jump at the chance and worry about vague hand-wavy "psychological burdens" later - or perhaps not ever if the new body didn't age...
What is the burden?
A burden I foresee is that people are going to have to choose between life extension and assisted suicide.
There might be some wider problems of overpopulation though, and longer lifespan might also cause increased income inequality. That's a separate question though.
Being suddenly young again would certainly be delightful for a while but there's a huge psychological burden that comes with living for a long time. While it may be possible to extend the life of the body, there are related philosophical considerations that the "live-forever" folks IMHO are flippantly dismissing. It makes me concerned that in the distant future we could find ourselves as a society with ever more problems that we're not equipped to deal with. We'll all likely be dead by then, but it makes for a thought.