> The plane is fundamentally unstable because of the huge engines

I'll leave the googling to you, but this isn't true. The plane isn't fundamentally unstable, and certainly not like a modern fly-by-wire fighter.

The 737 Max is unstable in the pitch axis. There is no debate about that.

It might help to read what aerodynamic instability actually means before making such a claim: https://en.wikipedia.org/wiki/Stability_derivatives

Outside of the typical flight envelope it absolutely is like a fly by wire fighter.

That's why there's an angle of attack sensor, to keep the plane outside of that failure range.