it is actually a good idea to hold for a very long time like 5 or 6 years, but 10 seems like a lot, he can make some good profit if things kept going well for crypto, it's the best option right now, i don't see bitcoin hitting some low price anytime soon, 25000$ can be the lowest bitcoin can get to.
We'll still not know what shall happen for the next years up to 10 years. But if someone thinks of that long, he can eventually sell even before reaching 10 years.
If someone hits the price that he wants at 3 years or lesser, he can just adjust his decision and not follow what he has set before. There's no bind in decisions as long as you won't regret when you sell or you do a buy back afterwards.