What is the need of taking profits overtime? what will you be using the profits to do? those are the questions and projecting 20-30 years will depend on the age of the hodler and if they have also reach their target of accumulation. The only time i can consider to take profits from my investment is after i must have accumulated to my satisfaction and have made a lot of profits which i know that if a take the profits i will invest it on something productive but taking profits and still keep it in Fiats or some stablecoins will make no sense at all so before intending to take profits you should be able to have a concrete plan of what to do with the profits you have gotten from your investments.