You're certainly entitled to your opinion. Me personally? I like it. I don't need my watch and my phone to make a sound at the same time. And I know people around me appreciate it. In fact, since I only use Haptics on my watch, no one near me hears anything, yet I'm notified just fine.
Whether Apple will change this in the future, I doubt it. It's been this way since the dawn of Apple Watch. But you are more than welcome to share your thoughts with Apple (this is after all a user to user only forum, which Apple doesn't participate in) by sharing your thoughts here --> Feedback - Watch - Apple
Note: I provided the link for Apple Watch feedback as this an issue about Apple Watch, not really about iPhone.