Yes many countries will decide to extradite for actions which are legal in said country.
I am French, and we recently convinced Scotland to extradite a French man who was denying the existence of the Holocaust and gaz chamber, which is something you could do in Scotland if you do it without violence.
So indeed it’s possible.
But I don’t think it’s the same as extraditing for a meme.
That's surprising, I hadn't heard about that. I had assumed that this was a blanket rule that generally applied to these treaties. I wonder how the UK justified it...
Also, one other differentiator here is that the man, as you described him, was a French citizen. The post up above implies extraditing foreigners from their countries of residence to the US, which is on a whole other level of insanity. Imagine what would've happened if France tried to extradite a Scottish man from within the UK for online posts.
I am French, and we recently convinced Scotland to extradite a French man who was denying the existence of the Holocaust and gaz chamber, which is something you could do in Scotland if you do it without violence.
So indeed it’s possible.
But I don’t think it’s the same as extraditing for a meme.