The code of conduct at the Maintainers Summit

You can only do so many events, and, as it was mentioned here, there already are a lot of conferences. That said, it's always helpful to know those people personally that you interact with regularly. While I'm not a kernel contributor, I can get very emotional when under pressure and had my experiences in that regard where I was seen as toxic by some people but personal interaction could clear up a lot of things (and I learned from those experiences as well). Local people also help because they tend to have a better understanding of your cultural aspects (us Europeans can routinely be harsh while not meaning it as badly as Californians or Asians may interpret it).
So, tl;dr, both local and in-your-contribution-area meetups make sense - if you have the time to attend and still contribute in a meaningful way.