Calling it a "bot" might be giving the person too much credit.

This is clearly some kid copy/pasting the same message over and over, without giving any thought to the situation. Given the behaviour he showcase, I highly doubt he would be able of creating an automated solution, run completely autonomously.

People like him, and others with childish behaviour, is bound to find their way to instances across the fediverse. The only solution to this is to turn the blind eye, which will make them lose interest, and move other places.

While I am just as annoyed as anyone else, mainly for him to waste compute-resources, I don't believe in outright banning. That would quickly become a slippery slope, potentially to justify silencing views you don't agree with, and restricting freedom of speech.

The best solution is just to ignore. Blocking works great for this tactic.