Medical technology is reducing the need for stem cells.
In the laboratory skin cells were treated with a virus, which was modified to ‘infect’ them with agents that function to convert the skin cells into precursors to brain cells. These cells can specialise into the three types of brain cell: neurons, oligodendrocytes and astrocytes. After laboratory research was carried out, the converted cells were injected into the brains of mice. These mice were bred to lack the protein myelin, which is important in aiding the transmission of messages in the brain. 10 weeks later, the precursor cells had specialised into oligodendrocytes, which made the myelin that the mice lacked.
Skin cells directly to brain cells, do not pass Go, do not create ethical issues. (And creating myelin, which is something that someone like me with MS raises their antennae over.)