Technology

Why would militaries invest in a billion dollar aircraft piloted by a highly trained aircraft pilot with years of training that cost millions of dollars that is probably paid millions over many years … when the pilot and his aircraft can be shot down by a $100,000 missile.

1. Force projection.
2. It ain't that easy to shoot down stealth aircraft.
3. Missiles that can successfully shoot down stealth aircraft cost several million dollars each.
4. Ground launch systems that can target and engage stealth aircraft, like the US Patriot System, are so horrifically expensive that no nation can afford enough of them to cover more than a fraction of its airspace. That means you need aircraft capable of engaging incoming enemy targets.

In short you are hideously naive.