Something like insider trading is a particularly grey area, because directors trade all the time with more knowledge than the public (how could they not), and leaks of information happen all the time without punishment. I don't know all the details of this particular case, but I'd be skeptical of taking the conviction at face value, given the willingness of some branches of the US government to openly lie to the public, distort the truth, bypass or neuter the judicial branch, and vindictively punish and vilify those who refuse to cooperate in illegality or blow the whistle on their activities.

More generally, whether you take a conviction as a proof of moral turpitude relates to how much faith you have that the justice system in a given country is operating in a just, transparent and fair manner. If you don't have that faith, a criminal conviction means nothing in moral terms.