His political nous is somewhat lacking at times. Hardly surprising considering his short time in politics. I don't think the sharks are circling though. And if they are it would be a big mistake by them. I think the chances of keeping National winning in that scenario are about as likely as Labour winning with Hipkins leading them.
Put it this way, he won them the election after almost halving Labours previous result, such a massive swing, put together a coalition agreement that continues to look pretty stable despite many people saying it would be a disaster, had zero honey moon period with constant personal attacks, implemented some tough but necessary measures, some controversial ones too. And despite all of that the polls remain stable, consumer confidence is up, business confidence is up, new trade deals done, inflation is falling, interest rates are falling and the government continue to move at pace getting things done (some say too fast). I see Luxon getting better and improving the more time he has spent in the role. Some seem to think he's not up to it, and they may be right, but if he's not up to it he seems to be faking it pretty well! It would have to be a fairly big shift in the polls for anyone in the party to consider a takeover. Funnier things have happened in politics before though