The same sorts of things that establish that blue stars don’t last billions of years. Either you accept what astronomers tell you about stars, or you don’t. Such as: smaller, cooler stars last far, far longer than big hot blue stars do. By reason that they emit less power, therefore, the fuel that they have lasts longer; if indeed blue stars are hundreds of thousands of times brighter than other stars, then, for the same mass they should last hundreds of thousands of times less, which places the lifespan of the smaller, less powerful stars into the billions of years. If stars lasted only 6000 years, they’d be going off like popcorn right now, don’t you think? Their numbers would all be coming up right about now. But they’re not, and we only see about one supernova per galaxy per year - out of the billions or trillions of stars that each galaxy has.