A couple of points.
Firstly, it's still not clear if there was a real impact on narcolepsy
Scientists have been trying to understand why some countries saw a rise in narcolepsy cases — and whether the spike was tied to the 2009 influenza pandemic.
www.statnews.com
Second, that even if there was, numbers are small, certainly far, far less than the impact of COVID.
Thirdly that there will be some risk with this vaccine, as with any other intervention, and also lack of intervention. We should be clear that anyone affected will be supported, and open about the fact that there are risks. But we shouldn't overstate them either - *most* vaccine side effects are short term, and none have anything like the long term risks we already know about from COVID infection. So the risk/benefit seems very clear.