Is Turkey’s KAAN fighter genuinely a 5th-generation aircraft?

No, it’s not.

It only looks like a 5th-generation fighter.

Let’s break it down simply:

Take a look at the intake — see the red line and the gap between the intake and the fuselage?
That’s called a caret inlet.

Its purpose is to separate the slower-moving boundary layer air from entering the engine, which could otherwise cause engine surges.

Caret inlets were acceptable in earlier generations of fighter jets, but 5th-generation aircraft prioritize stealth.