Definitely. In fact, I think the tribes we create in our community have a net negative effect. If you're happy with what you know and the apps you're building, cool. With that said, I believe progression is a fundamental aspect of human happiness and there's a big risk both to your career and the apps you build if you settle with what you already know. Never feel pressured to learn the cool new thing, but also don't encourage those who are building the future.