Navalny most certainly wasn’t stupid. He understood what he was getting into when he got on that flight back to Russia. My guess is that he hoped his arrest and detention would spark an uprising, which sadly didn’t materialize.
I would not have made the choice he did, but I’m also not as brave as he is. Fuck Putin.
Perhaps you moved from Europe to the States in the interim like I did.
Edit to add: sorry if this came off as snarky, was not my intention. Just wanted to point out that it’s not always so clear-cut. I created my Reddit account in 2008 when I lived in the Netherlands. Then I moved to the US in 2016 and became a citizen in 2019.