Your threat is bizarre (and quite frankly rude and probably against the yc rules).
There's nothing illegal about traveling to Crimea, only warnings from the US state department and maybe some other western nations.
From the Russian perspective, the Crimean territory is theirs. If you have valid Russian travel documents, you can enter. From the Ukrainian perspective, the Crimean territory is theirs and US citizens can spend up to an entire year in Ukraine visa-free.
You can't go to Crimea from Russia. It's against the international law. It's an illegal border crossing. Also, if you will try to access to GitHub from Crimean is's you will be blocked. And that your advice for going to Crimea from russia can bring troubles to people who will try to do that.
Its not illegal border crossing either because there is de facto no border there.
A dejure argument doesn't make sense because no matter which side of the argument you take, crossing into crimea isn't on its own illegal. At worst you're supposed to get a visa, but Ukraine has a pretty open policy so that is generally not required for tourism under 90 days.
Presumably if you're coming from Russia you already have a visa to be in Russia too
There's nothing illegal about traveling to Crimea, only warnings from the US state department and maybe some other western nations.
From the Russian perspective, the Crimean territory is theirs. If you have valid Russian travel documents, you can enter. From the Ukrainian perspective, the Crimean territory is theirs and US citizens can spend up to an entire year in Ukraine visa-free.