There are two perspectives to this situation and it depends on the individual's choice and what aligns the most with him.
1. One is as you said, he can take a gamble by holding the fun tokens and if luck strikes then he can get a better return.
2. You can sell now so that you can at least get something in return for the tokens because the price is likely to get to 1 satoshi and so something is better than nothing.
If I were in uneng position then I would go with the second option.
I would chose the option 2 IMO. As far as i gathered, FUN is tied to FBC and the "crew" around it. So if those projects are failing, FUN will fail as well.
Bitcoin on the other hand will hopefully grow and grow. So should be a no brainer, atleast from my POW