Let's talk code! What's in it for me? A journey through Javas 9-15

Java 15 got released last week (15th September). Your app is probably on Java 8. This is 7 releases! It's like jumping from Java 1 to Java 8! Insane amount of changes in the language, now is it?

Let's talk code. Let's go through Java 9, 10, 11 and all the others and let's talk code: how did the language change? What's in it for me? Skipping performance, security, JVM changes - since number of us will rarely have access to prod systems and even rarer would be for us to play admins.
I'll reiterate: this will be focused on everyday features, hepful in daily coding. I won't go (this time) into multithreading, perf fixes, deeper technical APIs. We won't have time either way. :D

So what's in it for me, a programmer? What language changes are there, that should interest me in new Java versions?
And once we have asked this questions it turns out... it's not that many. New releases are not that terrifying as most of us would assume.