Won't matter. You had the coins, you made gains on them, and then you lost them. The gains don't disappear. I suppose you could file a police report, and make a claim on insurance, or something like that. If you could somehow make it documented and legit from some authority that you actually did lose that money in a scam, or accident, then you could probably write off the loss, although there might be some limit to how much you can do that for.
Oops, just googled it, sorry no, you can't write off thefts on your taxes lol.