The "Bitcoin returning to $68,000 within 4 years" prediction is a very safe prediction. To be frank, Bitcoin staying at that price in the next four years would be after it must've done a fresh ATH that will surpass what it did in 2021. Four years from now will be 2026 and that should be two years after another Bitcoin halving. Every halving and post halving years have shown that Bitcoin would cap its previous ATH. $68k was for 2021, next halving in 2024 will be way above that; hopefully.