How feasible is preserving the dying for future revival?

Ask a biologist, or theorist, or someone following trends in technology. But a doctor? Not gonna have any better idea about that, than they do about what constitutes a minimum daily dose for a vitamin. Originally those things were set by polling doctors, and they were essentially set at random.

I think it's important to realise that because someone has knowledge in the field does not mean they can make prediction about completely unknown things.

There is a huge difference between "we don't see a reason why telekinesis would be impossible, but we have no clue how it would work" and "we have measurements and models of climate change that lead us to believe that if we don't change anything, our society will collapse".

How feasible is it to revive someone? We don't know. We haven't proven that it is impossible; just like telekinesis.