It is really that no brainer on what they would do or even kill satoshi to break down the morale of Bitcoin supporters but pretty sure it wont really be that something simple to happen.
It is really good to have on this way on which he decided to remain that anonymous and never tend to come out on the shadows.
Even if they catch Satoshi now, they won't be able to stop Bitcoin because of the way it was designed. The cryptocurrency has a lot of nodes and miners supporting it worldwide, so it would take a lot of time and effort to shut it down for good. Not even Satoshi would be able to do anything about it, as it's all about consensus.
Because Bitcoin is open source, any compromise on the Blockchain could easily trigger a new chain with its own set of rules. It's virtually unstoppable. They only chance governments would've had to stop Bitcoin was back in its very beginnings. Kudos to Satoshi remaining anonymous since day one. I hope he stays that way for the good of Bitcoin and the whole crypto/Blockchain space. Just my thoughts
Now it's too late to stop bitcoin because it has become too big to stop. But if at that time the government catches him, then I think it will be easier for them, it will be a lot easier to stop bitcoin. And I don't think they'll kill him, that's a negative thought. He is a genius, so the government will use his brilliant mind to work for them rather than kill him because if he dies, bitcoin will still live and thrive. In short, no matter what they say, it's too late to stop bitcoin .