Just so you know that we have short and long term trading.
Perhaps, short term trader did that and long term traders are usually holders.
Therefore I don't see any wrong if people will convert it to fiat and besides we don't know at what price they entered. What if they're already fine with the profit they got and want to be on a safe side. Thus, they can still buy again when it dump, that's the usual thing for a trader though.
We all have difference preference, so no need to rant.
In terms of crypto investment, it's free for people to do what they want. We can become short-term traders or become long-term investors. To be honest, both parties have their respective roles for the continuity of the crypto currency.