I don't think that long term holding is the safest choice because the market prices will not always going up. If you look at the price of Bitcoin way back November 2022, from $68k it went down to $17k, so for me it's not the safest and it's also time consuming, if the time has come you badly needed the money you are force to sell it at loss.
Indeed. The prices of crypto coins don't always rising. There is the time for a dump or decreasing a lot. According to 4 years cycle, there are 2 years for decreasing time for crypto coin prices. If we don't understand the cycle of crypto prices, it will be very risky to hold a long time. So, holding a long term will be safer if we understand the cycle and we hold trusted coins (BTC, ETH, ADA, etc).
For me, the safest is to sell all your assets when the market cycle comes to an end. There are four phases of market cycle: accumulation, advancing, distribution, and declining. If you know that we are in the distribution phase then that's the time to sell because declining will be next. And that time we don't know how deep the price will be.
Yes, it will be safe if we sell the coins when it is still in bullish season. Anyway, these phases includes in 4 years cycle. We need to learn the cycle and understand the potential of every coin for holding a long term. This will optimize the chance for profits and can prevent from the potential losses.