You are confusing organoids with "growing a brain". Organoids are a handful of cells of a given type derived from pluripotent stem cells and growing together. A neural organoid is nothing at all like a brain -- not even a brain slice. It is a loose connection of cells that have just enough context to somewhat behave natively or just not croak immediately (which is what most individual stem cells do when they differentiate in a petri dish).

It's like calling a 1 bit half-adder circuit a computer.

Organoids are very interesting scientifically because we will need to start with organoids to grow any sort of biological system. And they do behave closer to native than individual cells so they can be used to research things like cell metabolism and drug response. But they are not anywhere close to an organ. And unfortunately they aren't even close enough to replace animal testing, yet.