It may be a good time for you to watch this video,
https://www.youtube.com/watch?v=ZloHVKk7DHk <The amazing Math of Private keys> So, once people understand the math, they might also see how impossible it is for people to generate private keys that has been generated before.
The new buzzword for most newbies is Quantum computing and their first argument is that Quantum computers will reveal private keys for addresses that are filled with coins.
<They forget that stronger Algorithms exist that can be implemented, if computing power catch up to solve the current SHA256 algorithm.>
Do not get hyped up with future technologies that does not exist and also know new stronger algorithms are also developed to counter stronger computing power.